Genetic dissection of two Pakistani families with consanguineous localized autosomal recessive hypotrichosis (LAH)

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Objective(s): Genetic analysis of two consanguineous Pakistani families with localized autosomal recessive hypotrichosis was performed with the goal to establish genotype-phenotype correlation. Materials and Methods: Genomic DNA extraction had been done from peripheral blood samples. Extracted DNA was then subjected to PCR (polymerase chain reaction) for amplification. Linkage analysis was performed using 8% polyacrylamide gel. Candidate gene was sequenced after gene linkage supported at highly polymorphic microsatellite markers of the diseased region. Results: Both families were initially tested for linkage to known genes, which were involved in human hereditary hypotrichosis, by genotyping Highly polymorphic microsatellite markers. Family B showed partial linkage at P2RY5 gene on chromosome 13q14.11-q21.32; hence, all exonic regions and their introns boundaries were subjected to DNA sequencing for any pathogenic mutation. Conclusion:Both families were tested for linkage by genotyping polymorphic microsatellite markers linked to known alopecia loci. Family A excluded all known diseased regions that is suggestive of some novel chromosomal disorder. However, sequencing of P2RY5 gene in family B showed no pathogenic mutation.