Screening for mutations in two exons of FANCG gene in Pakistani population

Abstract

Background. Fanconi anemia is a rare autosomal recessive disorder of genetic instability. It is both molecularly and clinically, a heterogeneous disorder. Its incidence is 1 in 129,000 births and relatively high in some ethnic groups. Sixteen genes have been identified among them mutations in FANCG gene are most common after FANCA and FANCC gene mutations. Objective. To study mutations in exon 3 and 4 of FANCG gene in Pakistani population. Methods. Thirty five patients with positive Diepoxybutane test were included in the study. DNA was extracted and amplified for exons 3 and 4. Thereafter Sequencing was done and analyzed for the presence of mutations. Results. No mutation was detected in exon 3 whereas a carrier of known mutation c.307+1 G>T was found in exon 4 of the FANCG gene. Conclusion. Absence of any mutation in exon 3 and only one heterozygous mutation in exon 4 of FANCG gene points to a different spectrum of FA gene pool in Pakistan that needs extensive research in this area.