Analysis of a Haplotype Structure in a Non-coding Region of Human Chromosome 22

Haplotype structures are important in the study of human evolutionary history. These structures effectively simplify genome-wide association studies by reducing the number of mutations to be examined. Here, a haplotype block was analysed which located on 22q12.3 (Position: 34876961-34890077), a noncoding region of chromosome 22. Statistical tests suggested that the region is selectively neutral with a very low recombination rate. The genetic diversity analysis shows that the African population (AFR) has higher diversity than non-AFR populations. The results show that only 52 of 2,184 possible haplotypes are observed on this block. The haplotype distribution concentrates on 4~5 common haplotypes in non-African populations. However, the haplotypes are more evenly and more widely expressed in AFR. Due to genetic drift or sampling, these SNPs with strong LD(Linkage Disequilibrium) of this block is not observed in ASN. Results show that the strong LD structure was generated before humans left Africa.