Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0012872 (DNA marker)
 929 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Tuberous sclerosis (TSC) is an autosomal dominant disorder characterized by widespread hamartosis. Preliminary evidence of linkage between the TSC locus and markers on chromosome 9q34 was established, but subsequently disputed. More recently, a putative TSC locus on chromosome 11 has been suggested and genetic heterogeneity seems likely. Here we describe an approach combining multipoint linkage analysis and heterogeneity tests that has enabled us to obtain significant evidence for locus heterogeneity after studying a relatively small number of families. Our results support a model with two different loci independently causing the disease. One locus (TSC1) maps in the vicinity of the Abelson oncogene at 9q34 and a second locus (TSC2) maps in the region of the anonymous DNA marker Lam L7 and the dopamine D2 receptor gene at 11q23.
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PMID:Genetic heterogeneity in tuberous sclerosis. 197 47

The human dopaminergic system is a significant focal point of study in the fields of neuropsychiatry and pharmacology, plus it is also a promising nuclear DNA marker in studies of human genome diversity. In this study, we assayed six polymorphic markers in the dopamine D2 receptor gene (DRD2) in 482 unrelated individuals from nine ethnic populations of India. Our results demonstrate that the six markers are highly polymorphic in all populations and the constructed haplotypes show a high level of heterozygosity. Out of the eight possible three-site haplotypes, all populations commonly shared only three haplotypes. The haplotypes exhibited fairly high frequencies across multiple populations; Kurumba population showed all eight three-site haplotypes. The ancestral haplotype (B2-D2-Al) was observed at high frequency only in the Siddi population. Haplotypes based on all six markers revealed 16 haplotypes, out of which only 6 are most common with a frequency of greater than 5% in at least one of the nine populations. But only three haplotypes were shared by all nine populations with the cumulative frequency ranging from 80.8% (Kurumba) to 96.6% (Onge). Great variation in levels of linkage disequilibrium (LD) was detected, ranging from complete LD in the Badaga to virtually no LD in the Siddi. This range of LD likely reflects different population histories, such as African ancestry in the Siddi and recent founding events in the population isolates, Badaga and Kota.
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PMID:Allelic variation and haplotype structure of the dopamine receptor gene DRD2 in nine Indian populations. 1837 12