Human genomic DNA prepared from whole blood sample was analyzed to estimate allelic frequencies and genetic diversity at a hypervariable variable number of tandem repeats(VNTR) D1S80 locus in 127 Korean. Target DNA fragments were amplified by
polymerase
chain reaction(PCR) and separated by polyacrylamide gel electrophoresis.
@ES Then, the following results were obtained:
@EN 1. A total of 23 alleles were identified at this locus, which is the biggest number of alleles observed at this locus so far (cf. 16 from U.S. Caucasians and 15 from Finnish).
2. Sixty-two genotypes, included 3 homozygotes and 59 heterozygotes, out of a total of 276 probable genotypes were also observed, which might be resulted from the small sample size compared to the number of alleles observed in this study.
3. General pattern of allelic distribution was concordant with those observed in previous stueis from Finnish and U.S. Cauccasians where two alleles, M18 and M23, were observe most frequently and the rest of them were observe rare (<10%) with
the
exception of M30 allele(14.6%) in Korean. The number of M30 allele is suspected to be increased in Korean at or after the divergence of Korean from the hypothetical ancestor probably caused by random genetic drift such as founder effect or
bottleneck
effect.
4. Higher level of heterozygosity was obtained in Korean(H=0.866 and H=0.881) than in Finnish(N=0.77 and H=0.79) and U.S. Cauccasians(H=0.808 and H-0.797).
5. Population homogeneity was tested to corroborate the obtained population genetic parameters calculated based on the assumption of Hardy-Weinberg equilibrium, which could be done by Chi-square test between the observed umber of alleles and the
expected number of alleles, because of the small sample size analyzed in this study which resulted in high proportion of undetected genotypes (78.5%) and several genotypes significantly deviated from Hardy-Weinberg expectation in a sample
population.
The result suggests that samples were drawn from geneticically homogeneous population.
6. This study suggests that Korean is morediversified than Finnish and U.S. Cauccasians on the basis of the number of alleles and the level of heterozygosity, although Korean is known to be entirely composed of single race. Though we need more
informations from other Asian countries, this result suggests frequent gene flow from neighbor countries, which is also expected based on the old Korean history of frequent invasions from Japan andChina.
7. Based on the Hardy-Weinberg expectation, 216 out of 253 genotypes at D1S80 locus can be shared by less than 5 individuals among 1,000 unrelated individuals by chance. Our results suggest that the analysis of VNTR D1S80 locus can provide
prowerful,
but imperfect by itself, DNA markers for forensic study, which can be corroborated by analyzing additional VNTR loci.
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