Homozygosity Mapping in 8 Pakistani and Kashmiri Families for Known Alopecia Genes/Loci

The objective of the present study was to search for known alopecia genes/loci in highly inbred Pakistani and Kashmiri families. The term alopecia is broadly used for various forms of hereditary human hair loss, with large differences in age of inception, severity and coupled ectodermal abnormalities. Eight families with typical features of alopecia were included in the study and through linkage analysis, three of them were found linked with HR at 8p21.3, linkage interval at 12q21.2-q22 (containing several potential candidate genes) and ARWH1 locus (P2RY5) at 13q14.2 respectively. DNA sequence analysis in linked families revealed a C to G transition at nucleotide position 3978 (c. 3978C>G) in exon 18 of HR gene and a previously reported mutation, a homozygous 4 bp CATG insertion at nucleotide position 69 (c.69insCATG) in P2RY5 gene. The majority of the families which remained unlinked with markers for known alopecia genes highly signify the presence of novel gene/genes in causing the disease in these families and therefore, It is highly recommended that genome wide scan with microsatellite markers be performed to map the causative gene/genes.