ABSTRACT
Haplotype data estimated from 12 Y-chromosomal STRs were obtained from a sample of 207 unrelated male individuals from Sri Lanka. A total of 195 different haplotypes were identified, of which 183 were unique. Haplotype diversity was found be high (0.9948+/-0.0012) indicating increased discriminating capacity of these 12 Y-STR loci in forensic identification of Sri Lankan individuals. DYS385, representing two loci, was the most diverse marker (0.853). The lowest diversity (0.351) was observed with DYS391.
Subject(s)
Chromosomes, Human, Y , Genetics, Population , Haplotypes , Tandem Repeat Sequences , DNA Fingerprinting , Humans , Male , Polymerase Chain Reaction , Sri LankaSubject(s)
Genetic Variation , Microsatellite Repeats/genetics , Population Groups/genetics , Gene Frequency , Humans , Sri LankaABSTRACT
Allele frequencies and statistical parameters of forensic interest are presented for 11 autosomal microsatellites (CSF1PO, TPOX, TH01, D16S539, D13S317, D7S820, F13A, F13B, FESFPS, vWA and LPL) of four ethnic groups in Sri Lanka. A total of 513 unrelated individuals from Sinhalese, Sri Lankan Tamil, Indian Tamil and Sri Lankan Moor population groups were included. Sri Lanka is an island with a multi-ethnic population whose genetic composition has not been previously studied at the ethnic group level. All the 11 microsatellites were found to be highly polymorphic, with the combined power of exclusion being greater than 0.99999, in all four ethnic groups. Overall data analysis suggests that a single combined genetic database could be used for genetic-based identification purposes for the four ethnic groups.
Subject(s)
Ethnicity/genetics , Microsatellite Repeats/genetics , Alleles , Blood , DNA/genetics , DNA/isolation & purification , DNA Fingerprinting , Databases, Genetic , Forensic Genetics , Gene Frequency , Genetic Markers , Genetic Variation , Humans , Nucleic Acid Amplification Techniques , Polymerase Chain Reaction , Polymorphism, Genetic , Quality Control , Sri LankaABSTRACT
We report here, for the first time, a comparison of naturally acquired antibody responses to the 42 and 19 kDa C-terminal processing products of Plasmodium vivax Merozoite Surface Protein-1 assayed by ELISA using p42 and p19 baculovirus-derived recombinant proteins, respectively. Test populations comprised patients with microscopy confirmed acute P. vivax infections from two regions endemic for vivax malaria where low transmission and unstable malaria conditions prevail, and a non-endemic urban area, in Sri Lanka. The antibody prevalence to the two proteins, both at the individual and population levels, tend to respond more to p42 than to p19 in all test areas, where >14% of individuals preferentially recognized p42, compared with <2% for p19. In patients with no previous exposure to malaria, 21% preferentially recognized p42, whereas none exclusively recognized p19. A significantly lower prevalence of anti-p19 IgM, but not anti-p42 IgM, was observed among residents from endemic areas compared with their non-endemic counterparts. Individuals from both endemic areas produced significantly less anti-p19 IgM compared with anti-p42 IgM. IgG1 was the predominant IgG isotype for both antigens in all individuals. With increasing exposure to malaria in both endemic areas, anti-p19 antibody responses were dominated by the functionally important IgG1 and IgG3 isotypes, with a concurrent reduction in IgM that was lacking in the non-endemic residents. This antibody switch was also reflected for PvAMA-1 as we previously reported with the identical battery of sera. In contrast, the antibody switch for p42 was restricted to endemic residents with more extensive exposure. These results suggest that an IgM-dominated antibody response against the p42 polymorphic region in endemic residents may interfere with the development of an IgG-dominated "protective" isotype shift to p19, that may complicate vaccine development.