Age-related macular degeneration (AMD) is a common cause of severe vision loss. Identification of the genes involved in AMD will lead to a better understanding of this disease at the molecular level, which will eventually lead to early detection, prevention and treatment. Previously, we mapped the ARMD1 gene to 1q25-31 in a large family with AMD. Here, we narrow the ARMD1 locus to 14.9 Mb between LAMB2 and D1S3469, a region containing 50 known genes. Twenty candidate genes within this region were screened for mutations. Only one DNA variation, an A16,263G transition in exon 104 of HEMICENTIN-1, was found to segregate exclusively with the disease haplotype in members of this large family with AMD. This variation produces a non-conservative substitution of arginine for glutamine at amino acid position 5345 (Gln5345Arg). It was also identified in 11 other individuals, all of whom share a haplotype, which envelops HEMICENTIN-1, with the large AMD family. The affected status of all but one of those individuals conforms to the age-dependent penetrance observed in AMD. The amino acid at position 5345 of HEMICENTIN-1 was conserved as glutamine in eight species analyzed. RT-PCR analysis demonstrated that exon 104 of HEMICENTIN-1 is alternatively spliced in various cell types. Exclusive segregation of Gln5345Arg with the disease haplotype in this large family, amino acid conservation of glutamine at this position among mammals, the non-conservative nature of the substitution and similarities to EFEMP1 support the conclusion that HEMICENTIN-1 is the ARMD1 gene.
Studies of the biology, ecology, and status of the Pacific lamprey Lampetra tridentata may require effective means of tagging larval Pacific lampreys. However, few assessments of the methods suitable for tagging larval Pacific lampreys have been conducted. We evaluated the performance of visible implant elastomer (VIE) tags in larval Pacific lampreys, specifically testing the effects of elastomer treatment (uncured versus cured VIE) and inspection light source (ambient light versus blue light‐emitting diode [LED] flashlight) on tag detection in 40 larvae. Through day 251 after tagging, tag detection was 100% for both uncured and cured VIE tags observed under ambient light and blue LED light. Longevity of uncured VIE tags was assessed in a second cohort of 32 VIE‐tagged larval Pacific lampreys over a 2‐year captive rearing period. Percent VIE tag detection was 91% for red tags, 90% for orange tags, and 64% for green tags through day 699 after tagging. This study affirms that both uncured and cured VIE tags can be effectively used to tag larval Pacific lampreys. Tagging with uncured VIE is a convenient and economical alternative to cured VIE tagging, particularly when tagging over protracted periods or small sample sizes.
Marine protected areas (MPAs) have been heralded as the next important fisheries management tool. Predicted benefits include increased fish biomass, increased species diversity, and enhanced recruitment to the MPA itself, as well as to proximal areas. Whereas MPAs have in fact been shown to increase biomass and species diversity, evidence of enhanced recruitment has yet to be seen. If MPAs are significantly enhancing recruitment, one would expect to see the recruitment dominated by groups of siblings arising from highly productive females predicted to eventually reside in MPAs due to the protection afforded them. If occurring, such sibling-dominated recruitment could be identified by significantly fewer mtDNA haplotypes and significantly fewer singleton haplotypes in population samples of recruiting juveniles compared to adult populations. We investigated a new approach for potentially determining whether MPAs might be significantly enhancing recruitment to proximal areas of Santa Cruz and the Santa Catalina islands in the California Channel Islands, by seeking evidence of sibling-dominated juvenile recruitment in mitochondrial DNA haplotype data of the kelp bass Paralabrax clathratus. Our analyses found largely genetically mixed recruitment from the plankton, suggesting that recruitment to the sampled areas was not being measurably enhanced from point sources such as the nearby MPAs.KEY WORDS: mtDNA singleton fraction · Natal homing · Effective population size
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We describe the isolation and development of ten polymorphic microsatellite loci for western brook lamprey (Lampetra richardsoni). Two to nine alleles were observed per locus in a sample of 35 fish. Gene diversity ranged from 0.000 to 0.792 in six populations. Crossspecies amplification was successful as nine, seven and eight loci were polymorphic in Lampetra pacifica, Entosphenus hubbsi, and Entosphenus tridentatus, respectively. These markers will aid in evaluating the population structure of lamprey that are native to western North America.
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