Joseph Efthymiatos Stabile, Ph.D.

Delineation of discrete population segments of shortnose sturgeon Acipenser brevirostrum based on mitochondrial DNA control region sequence analysis
Wirgin, I; Grunwald, C; Stabile, J; Waldman, JR
2010 JUN ;11(3):689-708, Conservation genetics
Shortnose sturgeon Acipenser brevirostrum is federally listed as ''an endangered species threatened with extinction'' in the U.S. but its listing status is currently under review. As part of this process, the U.S. National Marine Fisheries Service will determine if shortnose sturgeon are divided into Distinct Population Segments (DPS) across its distribution. In this regard, we sought to determine if shortnose sturgeon occur in genetically 'discrete population segments,' and if so, the boundaries of each. We used mitochondrial DNA (mtDNA) control region sequence analysis to assess the genetic discreteness of 14 of 19 river populations that were recommended as DPS in the 1998 Final Recovery Plan for Shortnose Sturgeon. Nine of the 14 proposed DPS proved significantly discrete (P < 0.05 after Bonferoni correction) from both of their bracketing populations, the exceptions being those in the Penobscot River, Chesapeake Bay, Cooper River, and Ogeechee River (our sample from the Cape Fear River was insufficient to statistically analyze). Haplotype frequencies in the newly 'rediscovered' Penobscot River collection were almost identical to those in the proximal Kennebec River system. Genetic data in combination with tagging results suggest that shortnose sturgeon in the Penobscot River are probably migrants from the Kennebec. Likewise, shortnose sturgeon found today within the Chesapeake Bay appear to be migrants from the Delaware River. While haplotype frequencies in the remnant Santee River population in Lake Marion differed significantly from those in nearby Winyah Bay, they did not differ significantly from those in the Cooper River. This suggests that the Cooper River harbors descendants of the Santee River population that are unable to access their historical spawning locales. The Ogeechee River collection was not genetically distinct from that in the nearby Savannah River, suggesting that it may host descendants of hatchery-reared individuals of Savannah River ancestry. Our genetic results indicate that most, but not all, rivers with shortnose sturgeon host genetically discrete populations, constituting important information in the consideration of DPS designations. However, shortnose sturgeon migrations through coastal waters to proximal rivers and release of hatchery-reared fish may confound results from genetic studies such as ours and lead to the possible misidentification of discrete population segments
— id: 109967, year: 2010, vol: 11, page: 689, stat: Journal Article,

Conservation of Atlantic sturgeon Acipenser oxyrinchus oxyrinchus: delineation of stock structure and distinct population segments
Grunwald, C; Maceda, L; Waldman, J; Stabile, J; Wirgin, I
2008 JUL-AUG ;9(5):1111-1124, Conservation genetics
The anadromous Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, a wide-ranging species along the Atlantic Coast of North America, is being considered for federal listing under the U.S. Endangered Species Act. Identification of distinct population segments (DPS) is necessary but problematic for highly vagile species such as Atlantic sturgeon which may spend a high proportion of their lives outside of their natal estuaries. Characterization of genetic differentiation and estimates of gene flow provide a quantitative measure of the number of DPS into which species could be divided over their distribution and the reproductive independence of each unit. We sequenced a portion of the mitochondrial DNA control region to characterize population structure and gene flow across all naturally reproducing populations from which specimens could be obtained. We then considered these genetic data along with ancillary information on life history characteristics, historical fisheries data, and trajectories of abundance to determine the number of DPS into which this species should be divided. Our results suggest that philopatry is high for Atlantic sturgeon and that each U.S. estuary analyzed hosts genetically distinct populations of Atlantic sturgeon. We conclude that at least nine DPS of Atlantic sturgeon exist along the Atlantic Coast of the U.S. In contrast, the Atlantic Sturgeon Status Review Team has proposed a five DPS scheme for this subspecies based largely on results from nuclear DNA microsatellites, but with fewer populations represented and lower samples sizes. These different conclusions illustrate the somewhat arbitrary nature of the DPS concept, at least as applied to Atlantic sturgeon
— id: 86667, year: 2008, vol: 9, page: 1111, stat: Journal Article,

Genetic evidence for relict Atlantic sturgeon stocks along the mid-Atlantic coast of the USA
Wirgin, I; Grunwald, C; Stabile, J; Waldman, J
2007 NOV ;27(4):1214-1229, North American journal of fisheries management
The Atlantic sturgeon Acipenser oxyrinchus oxyrinchus is a highly migratory anadromous acipenserid that is distributed along the Atlantic coast of North America. The abundance of Atlantic sturgeon has not increased appreciably in recent years despite the imposition of a moratorium on its harvest in U.S. waters in 1998. Two measures being considered to restore depleted or extirpated populations are designation of Atlantic sturgeon as federally endangered under the U.S. Endangered Species Act and the use of hatchery-reared fish to supplement natural reproduction. Implementation of these approaches requires detailed knowledge of this species' population structure. Previous genetic stock identification studies failed to address the discreteness of Atlantic sturgeon populations along the U.S. mid-Atlantic coast that historically supported two of the largest fisheries for the species. We used mitochondrial DNA (mtDNA) control region sequence data to elucidate the population structure of Atlantic sturgeon in the Delaware River and two tributaries of Chesapeake Bay, the James and York rivers. Haplotypes of individuals from these rivers were compared with those from 14 other estuaries. Levels of mtDNA diversity were moderately high; 45 haplotypes were observed among the 860 specimens analyzed. We found significant temporal instability of haplotypes among collections of subadults made in different years from the Delaware River, including haplotypes not seen elsewhere and others that were common in the adjoining Hudson River and Albemarle Sound. Ibis finding suggests that natural reproduction of a genetically distinct population still occurs in the Delaware River, but that it also hosts migrant subadults from elsewhere. In contrast, temporal instability of haplotype frequencies was absent among collections from different years in the Hudson River. Although private haplotypes were absent from the James and York River samples, significant frequency differences between these collections and those from elsewhere suggest that some tributaries of Chesapeake Bay still host genetically unique populations of Atlantic sturgeon
— id: 75692, year: 2007, vol: 27, page: 1214, stat: Journal Article,

Range-wide population structure of shortnose sturgeon Acipenser brevirostrum based on sequence analysis of the mitochondrial DNA control region
Wirgin, I; Grunwald, C; Carlson, E; Stabile, J; Peterson, DL; Waldman, J
2005 JUN ;28(3):406-421, Estuaries
Riverine populations of shortnose sturgeon (Acipenser brevirostrum) once occurred in rivers and estuaries along the east coast of North America from the St. John River, New Brunswick, to the St. Johns River, Florida. Within this range, 19 population segments were identified by the U.S. Federal Shortnose Sturgeon Recovery Team; empirical data supporting this structure is limited. We obtained samples from 11 (12 including a small sample from the Cape Fear River, North Carolina) of these population segments and used PCR and direct sequence analysis of 440 base pairs of the mitochondrial DNA (mtDNA) control region to define the coast-wide genetic population structure of shortnose sturgeon. Collections from most population segments exhibited significant differences in haplotype frequencies with their nearest neighbors, including from the Ogeechee and Savannah Rivers, Georgia (despite the known movement of hatchery reared offspring from the Savannah into the Ogeechee River). Collections from the Chesapeake Bay and Delaware River exhibited similar haplotype frequencies, suggesting that specimens collected in the Chesapeake Bay had dispersed from the Delaware River. Collections from the Kennebec River and Androscoggin River within a hypothesized single population segment did not exhibit significant differentiation of mtDNA haplotype frequencies. Haplotype frequencies were almost identical between collections from above and below the Holyoke Dam on the Connecticut River, indicating that these aggregations should be managed as a single unit. Our results support the population segment status afforded to shortnose sturgeon in at least the following 9 systems; St. John River, Kennebec-Androscoggin Rivers, upper-lower Connecticut River, Hudson River, Delaware River-Chesapeake Bay, Pee Dee River, Cooper River, Savannah River, and Ogeechee-Altamaha Rivers
— id: 57650, year: 2005, vol: 28, page: 406, stat: Journal Article,

Development and use of a simple DNA test to distinguish larval redhorse species in the Oconee River, Georgia
Wirgin, I; Currie, DD; Stabile, J; Jennings, CA
2004 FEB ;24(1):293-298, North American journal of fisheries management
The robust redhorse Moxostoma robustum is a rare catostomid species that was recently 'rediscovered' in three Atlantic slope drainages in the southeastern United States, including the Oconee River, Georgia. Adult population size in the Oconee River is declining, and the population may be senescent due to recruitment failure. Evaluation of the environmental factors affecting the success of young life stages requires the ability to distinguish robust redhorse larvae from those of other redhorse species in the Oconee River. The use of morphological approaches, including size at collection date, have proven to be problematic in distinguishing larval robust redhorse from notchlip redhorse M. collapsum from the Oconee River. We developed a mitochondrial DNA (mtDNA) assay to distinguish between reference adults of these two redhorse species from the Oconee, Savannah, and Pee Dee rivers. This mtDNA assay was then applied to unknown larval redhorse collections from the Oconee River. In one collection, discordance was revealed in 40% of the individual larvae identified by both size at collection date and mtDNA. Of these, 75% of the fish thought to be notchlip redhorses based on size at date of collection exhibited robust redhorse mtDNA haplotypes. These results illustrate the utility of DNA techniques in characterizing the young life stages of fish and suggest that earlier surveys underestimated the abundance of larval robust redhorses in the Oconee River
— id: 42465, year: 2004, vol: 24, page: 293, stat: Journal Article,

Population genetics of shortnose sturgeon Acipenser brevirostrum based on mitochondrial DNA control region sequences
Grunwald, C; Stabile, J; Waldman, J R; Gross, R; Wirgin, I
2002 Oct;11(10):1885-1898, Molecular ecology
Shortnose sturgeon is an anadromous North American acipenserid that since 1973 has been designated as federally endangered in US waters. Historically, shortnose sturgeon occurred in as many as 19 rivers from the St. John River, NB, to the St. Johns River, FL, and these populations ranged in census size from 10(1) to 10(4), but little is known of their population structure or levels of gene flow. We used the polymerase chain reaction (PCR) and direct sequence analysis of a 440 bp portion of the mitochondrial DNA (mtDNA) control region to address these issues and to compare haplotype diversity with population size. Twenty-nine mtDNA nucleotide-substitution haplotypes were revealed among 275 specimens from 11 rivers and estuaries. Additionally, mtDNA length variation (6 haplotypes) and heteroplasmy (2-5 haplotypes for some individuals) were found. Significant genetic differentiation (P < 0.05) of mtDNA nucleotide-substitution haplotypes and length-variant haplotypes was observed among populations from all rivers and estuaries surveyed with the exception of the Delaware River and Chesapeake Bay collections. Significant haplotype differentiation was even observed between samples from two rivers (Kennebec and Androscoggin) within the Kennebec River drainage. The absence of haplotype frequency differences between samples from the Delaware River and Chesapeake Bay reflects a probable current absence of spawning within the Chesapeake Bay system and immigration of fish from the adjoining Delaware River. Haplotypic diversity indices ranged between 0.817 and 0.641; no relationship (P > 0.05) was found between haplotype diversity and census size. Gene flow estimates among populations were often low (< 2.0), but were generally higher at the latitudinal extremes of their distribution. A moderate level of haplotype diversity and a high percentage (37.9%) of haplotypes unique to the northern, once-glaciated region suggests that northern populations survived the Pleistocene in a northern refugium. Analysis of molecular variance best supported a five-region hierarchical grouping of populations, but our results indicate that in almost all cases populations of shortnose sturgeon should be managed as separate units
— id: 39587, year: 2002, vol: 11, page: 1885, stat: Journal Article,

Impacts of life history and biogeography on the genetic stock structure of Atlantic sturgeon Acipenser oxyrinchus oxyrinchus, Gulf sturgeon A-oxyrinchus desotoi, and shortnose sturgeon A- brevirostrum
Waldman, JR; Grunwald, C; Stabile, J; Wirgin, I
2002 DEC ;18(4-6):509-518, Journal of applied ichthyology
Non-genetic data indicate that Atlantic sturgeon ( Acipenser oxyrinchus oxyrinchus) are substantially dispersive in marine waters, possibly remaining out of their natal rivers for many years at a time. Gulf sturgeon (A. o. desotoi) only appear to use marine waters during cooler months, summering in rivers. Shortnose sturgeon (A. brevirostrum) are highly residential in rivers, but do sometimes go to sea and move between rivers. We used the polymerase chain reaction (PCR) and direct sequence analysis of a portion of the mitochondrial DNA ( mtDNA) control region to examine stock structure, haplotypic diversity, and gene flow (N-fm) among these taxa, hypothesizing that gene flow would be highest in Atlantic sturgeon. Stock structuring was strong within all three taxa most river populations supported genetically distinct stocks of sturgeons. Estimates of gene flow among regions were low to moderate in comparison with other anadromous fishes, suggesting that homing fidelity within all three taxa is high. However, average gene flow in Atlantic sturgeon was almost three times higher than in shortnose sturgeon, which somewhat exceeded gene flow values for Gulf sturgeon. Levels and patterns of haplotype diversity differed dramatically between the largely-sympatric Atlantic and shortnose sturgeon. Atlantic sturgeon exhibited a cline in haplotype diversity with monomorphism or very low diversity observed in northern, previously glaciated populations and moderate to high levels of diversity in southern, non-glaciated populations. In contrast, no difference in haplotype diversity and little sharing of haplotypes was observed between northern and southern populations of shortnose sturgeon. We hypothesize that the greater mtDNA diversity in northern populations of shortnose sturgeon resulted from their use of a glacial refugium that was not occupied by Atlantic sturgeon. Gulf sturgeon show much lower gene flow than Atlantic sturgeon. This may be due to their more temporally and geographically constrained marine migrations, which may reduce the opportunities for straying, and a need to return to assured summer thermal refugia. A new finding is the probable existence of a native, genetically-distinct Atlantic sturgeon stock in the James River, which has rami cations for restoration strategies for the species in Chesapeake Bay
— id: 33274, year: 2002, vol: 18, page: 509, stat: Journal Article,

Comparison of mitochondrial DNA control region sequence and microsatellite DNA analyses in estimating population structure and gene flow rates in Atlantic sturgeon Acipenser oxyrinchus
Wirgin, I; Waldman, J; Stabile, J; Lubinski, B; King, T
2002 DEC ;18(4-6):313-319, Journal of applied ichthyology
Atlantic sturgeon Acipenser oxyrinchus is large, long-lived, and anadromous with subspecies distributed along the Atlantic ( A. oxyrinchus oxyrinchus) and Gulf of Mexico (A. o. desotoi) coasts of North America. Although it is not certain if extirpation of some population units has occurred, because of anthropogenic influences abundances of all populations are low compared with historical levels. Informed management of A. oxyrinchus demands detailed knowledge of its population structure, levels of genetic diversity, and likelihood to home to natal rivers. We compared the use of mitochondrial DNA ( mtDNA) control region sequence and microsatellite nuclear DNA (nDNA) analyses in identifying the stock structure and homing fidelity of Atlantic and Gulf coast populations of A. oxyrinchus. The approaches were concordant in that they revealed moderate to high levels of genetic diversity and suggested that populations of Atlantic sturgeon are highly structured. At least six genetically distinct management units were detected using the two approaches among the rivers surveyed. Mitochondrial DNA sequences revealed significant cline in haplotype diversity along the Atlantic coast with monomorphism observed in Canadian populations. High levels of nDNA diversity were also observed among populations along the Atlantic coast, including the two Canadian populations, probably resulting from the more rapid rate of mutational and evolutionary change at microsatellite loci. Estimates of gene flow among populations were similar between both approaches with the exception that because of mtDNA monomorphism in Canadian populations, gene flow estimates between them were unobtainable. Analyses of both genomes provided high resolution and confidence in characterizing the population structure of Atlantic sturgeon. Microsatellite analysis was particularly informative in delineating population structure in rivers that were recently glaciated and may prove diagnostic in rivers that are geographically proximal along the south Atlantic coast of the US
— id: 33273, year: 2002, vol: 18, page: 313, stat: Journal Article,

Genetic divergence of robust redhorse Moxostoma robustum (Cypriniformes Catostomidae) from the Oconee River and the Savannah River based on mitochondrial DNA control region sequences
Wirgin, I; Oppermann, T; Stabile, J
2001 MAY 1 ;15(2):526-530, Copeia
A Memorandum of Understanding, which formed the Robust Redhorse Conservation Committee (RRCC), was developed and adopted by concerned stakeholders in Georgia, South Carolina, and North Carolina to attempt recovery of the recently 'rediscovered,' and rare, robust redhorse Moxostoma robustum, As part of the con servation program, genetic analyses of robust redhorse populations were needed to facilitate responsible hatchery programs that could be used to supplement natural reproduction in declining populations and to reestablish populations in rivers in which it may have historically been present. We analyzed mtDNA control region sequences in robust redhorse from the Oconee and Ocmulgee Rivers in the Altamaha River drainage and the Savannah River to determine the genetic relatedness of these populations to guide restoration efforts. Fixed differences in mtDNA haplotypes were found between robust redhorse from the two drainages that strongly argues for the designation of these populations as Evolutionarily Significant Units and against the interstock transfer of fish. Further studies will be needed to evaluate the full significance of these differences and associated management implications
— id: 55080, year: 2001, vol: 15, page: 526, stat: Journal Article,

Genetic structure of Atlantic sturgeon populations based on mitochondrial DNA control region sequences
Wirgin, I; Waldman, JR; Rosko, J; Gross, R; Collins, MR; Rogers, SG; Stabile, J
2000 MAR ;129(2):476-486, Transactions of the American Fisheries Society
The Atlantic sturgeon Acipenser oxyrinchus oxyrinchus has a latitudinally broad distribution along the east coast of North America, with extant populations occurring from the Saint Lawrence River to rivers in southern Georgia. This species once supported intensive caviar-based fisheries that resulted in overharvest and sharply reduced population abundances; presently, directed commercial fishing for Atlantic sturgeon is banned in U.S. waters. We sequenced a 203-base-pair section of the mitochondrial DNA (mtDNA) control region of 322 Atlantic sturgeon specimens from 11 river systems across their range to elucidate their stock structure. We found a pronounced latitudinal dine in the number of composite mtDNA haplotypes and in haplotypic diversity, which increased from north to south, from previously glaciated and subsequently recolonized systems to the portion of their range unglaciated during the Pleistocene. The observed number of haplotypes per population ranged from 1 haplotype in each of the two northernmost population samples to 17 in the sample from the Savannah River. Haplotypic diversity ranged from 0.0 to 0.90. The greater genetic diversity within and among southern populations is likely a product of the persistence of these populations through the Pleistocene and to the faster mutation rates associated with their shorter generation times. Of 39 composite mtDNA haplotypes found, 64% were unique to particular populations. Monomorphism of the two Canadian populations suggested a strong founder effect. Three haplotypes unique to northern populations were probably the result of base substitutions that occurred within the past 10,000 years. In contrast with an earlier study, we found stock structure among southern populations and evidence of at least seven generic stocks across this subspecies' range
— id: 54551, year: 2000, vol: 129, page: 476, stat: Journal Article,

High frequency of K-ras mutations in pink salmon embryos experimentally exposed to Exxon Valdez oil
Roy, NK; Stabile, J; Seeb, JE; Habicht, C; Wirgin, I
1999 JUL ;18(7):1521-1528, Environmental toxicology & chemistry
Previous studies demonstrated reduced survivorship of pink salmon embryos from populations in Prince William Sound, Alaska, USA, that were exposed to Exxon Valdez-released oil compared with populations from matched nonoiled streams. Survivorship was also significantly decreased in embyros from lineages that were oiled in Prince William Sound and reared in clean water under controlled hatchery conditions compared with the descendants of nonoiled lineages. This suggests that the effect of oiling on pink salmon populations was persistent and could be transmitted intergenerationally. However, the ability of environmentally released oil to cause DNA sequence alterations in natural populations has vet to be demonstrated. We used polymerase chain reaction analysis to screen for alterations in the K-ras oncogene in DNA from pink salmon embryos that were exposed under controlled laboratory conditions to weathered Prudhoe Bay crude oil. Polymerase chain reaction and direct DNA sequence analyses were used to identify mutational hotspots within exons 1 and 2 of K-ras. and 3' primer mismatch analysis was used to determine the frequency of mutations in the 30 offspring of two families of pink salmon that were experimentally exposed to oiled or clean gravel. Mutations were only observed at codons 12, 13, and 61 of K-ras, sites that are frequently mutated in animal and human tumors. All mutations resulted in deduced amino acid substitutions. As expected, in all individuals exhibiting mutations, the copy number of the normal allele exceeded that of the mutated allele. The frequencies of mutations in oiled embryos at K-ras exons 1 and 2 were 68 and 41%, respectively. K-ras mutations were not observed in siblings that were exposed to clean gravel or in the parents of the two experimental matings. These results indicate that exposure of pink salmon embryos to weathered Prudhoe Bay crude oil under controlled laboratory conditions can elicit somatic cell mutations in high frequency at mutational hotspots in genes such as K-ras. However the frequency of these events in oiled natural populations of pink salmon and other vulnerable species in Prince William Sound and the heritability of these mutations within oiled lineages have yet to be evaluated
— id: 54023, year: 1999, vol: 18, page: 1521, stat: Journal Article,

Comparison of the efficacy and safety of 2% dorzolamide and 0.5% betaxolol in the treatment of elevated intraocular pressure
Rusk C; Sharpe E; Laurence J; Polis A; Adamsons I; Baron JG; Cacioppo LR; Dickson JB; DuBiner H; Gieser DK; Greenberg M; Karp DW; Kottler M; Levenson JH; Lewis RA; Liss RP; Ostrov CS; Prywes A; Read FW; Rice R; Sall KN; Sandberg JS; Santangelo M; Sharpe E; Sherwood M; Spirn FH; Stabile J; Stewart W; Vela A
1998 ;20(3):454-466, Clinical therapeutics
A multicenter, parallel-design, randomized, double-masked study was conducted to compare the efficacy and safety of 2% dorzolamide with those of 0.5% betaxolol in the treatment of elevated intraocular pressure (IOP). A total of 311 adults with ocular hypertension or open-angle glaucoma were randomly allocated to receive either 2% dorzolamide administered topically TID or 0.5% betaxolol administered topically BID plus placebo administered topically QD for 12 weeks. After the washout of previous ocular hypotensive drugs, patients with IOP <=23 mm Hg in at least one eye at 10 AM or 4 PM on study day 1 were randomly allocated to receive one of the study treatments. Throughout the study, IOP was measured 2 and 8 hours after instillation of study medication for the morning peak effect (hour 2) and afternoon trough effect (hour 8). After 12 weeks of therapy, the mean change in IOP was not significantly different between the dorzolamide and betaxolol treatment groups at hour 8 (-3.6 mm Hg in both groups) or hour 2 (-5.4 vs -5.3 mm Hg, respectively). The differences between treatments (and 95% CIs associated with these differences) in mean IOP changes from baseline were 0.02 mm Hg (- 0.870 to 0.901) for hour 8 and -0.14 mm Hg (-0.959 to 0.685) for hour 2. The ocular adverse experience (AE) most frequently reported by patients was ocular burning and/or stinging, and the most frequently reported nonocular AEs were taste perversion, upper respiratory infection, and headache. Only the incidence of taste perversion was significantly different between treatment groups (14.6% for the dorzolamide group and 0.0% for the betaxolol group). Two percent of patients in each treatment group discontinued the study due to AEs. This study confirmed the similar IOP-lowering effect of 2% dorzolamide and 0.5% betaxolol. Both treatments were generally well tolerated, and their safety profiles were similar
— id: 15969, year: 1998, vol: 20, page: 454, stat: Journal Article,

An evaluation of introgression of Atlantic coast striped bass mitochondrial DNA in a Gulf of Mexico population using formalin-preserved museum collections
Wirgin I; Maceda L; Stabile J; Mesing C
1997 Oct;6(10):907-916, Molecular ecology
Striped bass Morone saxatilis populations in drainages along the Gulf of Mexico coast (Gulf) were depleted in the 1950s and 1960s, probably because of anthropogenic influences. It is believed that only the Apalachicola-Chattahoochee-Flint (A-C-F) river system continually supported a naturally reproducing population of Gulf lineage. Striped bass juveniles of Atlantic coast (Atlantic) ancestry were introduced to restore population abundances in the A-C-F from the late 1960s to the mid 1970s and in many other Gulf rivers from the 1960s to the present. We previously identified mtDNA polymorphisms that were unique to approximately 60% of striped bass from the A-C-F and which confirmed the continued successful natural reproduction of striped bass of Gulf maternal ancestry within the system. However, the genetic relatedness of the extant A-C-F population to 'pure' Gulf striped bass was not addressed. In this study, we determined the frequency of a diagnostic mtDNA XbaI polymorphism in samples of 'pure' Gulf striped bass that were collected from the A-C-F prior to the introduction of Atlantic fish, that were obtained from museum collections, and that were originally preserved in formalin. PCR primers were developed that allowed for amplification of a 191-bp mtDNA fragment that contained the diagnostic XbaI restriction site. Using RFLP and direct sequence analyses of the PCR amplicons, we found no significant differences in mtDNA XbaI genotype frequencies between the archived samples and extant A-C-F samples collected over a 15-year period. This indicates that significant maternally mediated introgression of Atlantic mtDNA genomes into the A-C-F gene pool has not occurred. Additionally, we found no evidence of the unique Gulf mtDNA genotype in striped bass from extant populations in Texas, Louisiana and the Mississippi River. These results highlight the importance of the A-C-F as a repository of striped bass to restore extirpated Gulf populations and the potential use of museum collections in retrospective population studies
— id: 57351, year: 1997, vol: 6, page: 907, stat: Journal Article,

Mixed-stock analysis of Atlantic coast striped bass (Morone saxatilis) using nuclear DNA and mitochondrial DNA markers
Wirgin, II; Waldman, JR; Maceda, L; Stabile, J; Vecchio, VJ
1997 DEC ;54(12):2814-2826, Canadian journal of fisheries & aquatic sciences
Striped bass (Morone saxatilis) stocks comingle along the northeastern United States and Canadian coasts and support mixed-stock fisheries in which stock compositions fluctuate widely. Many approaches to stock analysis of these populations have been tried. The recent use of mitochondrial DNA (mtDNA) haplotype frequency data showed promising results, despite low levels of mtDNA variation; to improve resolution, we used a single-copy nuclear DNA (nDNA) probe with mio mtDNA markers (major length variants and Tag I variants), alone or in combination. Striped bass reference collections were from the Hudson River and Chesapeake Bay, and mixed-stock collections (1989 and 1991) were from eastern Long Island, New York. The combination of the nDNA and mtDNA major length variant data provided lower but still quite high resolution potential (D-st = 0.417) in mixed-stock analysis (1991 collection) than the combination of all three markers (D-st = 0.552). However, unlike the Hudson River stock, the Chesapeake Bay stock is composed of multiple substocks that vary significantly in the frequencies of Taq I variants; this among-substock variation destabilizes the Chesapeake Bay reference data set and the resultant mixed-stock estimates. Thus, we recommend an approach based on composite nDNA and mtDNA major length variant markers
— id: 53542, year: 1997, vol: 54, page: 2814, stat: Journal Article,

Molecular analysis in the conservation of sturgeons and paddlefish
Wirgin, Isaac I.; Stabile, Joseph E.; Waldman, John R.
1997 ;48(1-4):385-398, Environmental Biology of Fishes
Sturgeon and paddlefish populations worldwide have declined because of anthropogenic influences. The structure and magnitude of genetic diversity of natural populations serves to buffer these fishes against environmental variation and should be maintained. Modern molecular biological techniques provide the ability to sensitively characterize and quantify the extent of genetic variation in natural populations. We provide a summary of those problems in sturgeon population biology that are amenable to investigation with DNA approaches, and their applications to date. These have included genetic identification and discrimination of taxa, identification of hybrids, stock identification, mixed-stock analysis, and estimation of gene flow and homing fidelity. To date, almost all studies have been restricted to North American fauna. Improvements to these technologies, including nondestructive sampling, should permit more widespread application of molecular approaches to problems of acipenseriform conservation. We suggest that the use of more sensitive molecular tools such as analyses of hypervariable repetitive and non-coding single copy nuclear DNA may assist management even in those taxa which exhibit overall low levels of genetic diversity
— id: 98800, year: 1997, vol: 48, page: 385, stat: Journal Article,

Genetic divergence between Acipenser oxyrinchus oxyrinchus and A-o-desotoi as assessed by mitochondrial DNA sequencing analysis
Ong, TL; Stabile, J; Wirgin, I; Waldman, JR
1996 MAY 16 ;32(2):464-469, Copeia
— id: 52895, year: 1996, vol: 32, page: 464, stat: Journal Article,

Stock structure and homing fidelity in Gulf of Mexico sturgeon (Acipenser oxyrinchus desotoi) based on restriction fragment length polymorphism and sequence analyses of mitochondrial DNA
Stabile J; Waldman JR; Parauka F; Wirgin I
1996 Oct;144(2):767-775, Genetics
Efforts have been proposed worldwide to restore sturgeon populations through the use of hatcheries to supplement natural reproduction and to reintroduce sturgeon where they have become extinct. We examined the population structure and inferred the extent of homing in the anadromous Gulf of Mexico (Gulf) sturgeon (Acipenser oxyrinchus desotoi). Restriction fragment length polymorphism and control region sequence analyses of mitochondrial DNA (mtDNA) were used to identify haplotypes of Gulf sturgeon specimens obtained from eight drainages spanning the subspecies' entire distribution from Louisiana to Florida. Significant differences in haplotype frequencies indicated substantial geographic structuring of populations. A minimum of four regional or river-specific populations were identified (from west to east): (1) Pearl River, LA and Pascagoula River, MS, (2) Escambia and Yellow rivers, FI, (3) Choctawbatchee River, FL and (4) Apalachicola Ochlockonee, and Suwannee rivers, FL. Estimates of maternally mediated gene flow between any pair of the four regional or river-specific stocks ranged between 0.15 to 1.2. Tandem repeats in the mtDNA control region of Gulf sturgeon were not perfectly conserved. This result, together with an absence of heteroplasmy and length variation in Gulf sturgeon mtDNA, indicates that the molecular mechanisms of mtDNA control region sequence evolution differ among acipenserids
— id: 12528, year: 1996, vol: 144, page: 767, stat: Journal Article,