A Novel Locus for Autosomal Recessive Retinitis Pigmentosa in a Consanguineous Pakistani Family Maps to Chromosome 2p
Accepted 21 December 2009. published online 15 March 2010.
Objective
To identify a disease locus for autosomal recessive retinitis pigmentosa in a consanguineous Pakistani family.
Design
Prospective linkage study.
Methods
Blood samples were collected and genomic DNA was extracted. A genome-wide scan was performed using 382 polymorphic microsatellite markers on genomic DNA from 4 affected and 5 unaffected family members, and logarithm of odds scores were calculated.
Results
A maximum 2-point logarithm of odds score of 3.14 at θ = 0 was obtained for marker D2S165 during the genome-wide scan. Fine mapping markers identified a 20.92-cM (19.98-Mb) interval flanked by D2S149 and D2S367 that cosegregates with the disease phenotype. Haplotype analyses further refined the critical interval, distal to D2S220 in a 12.31-cM (13.35-Mb) region that does not harbor any genes that previously have been associated with retinitis pigmentosa.
Conclusions
Linkage analysis identified a new locus for autosomal recessive retinitis pigmentosa that maps to chromosome 2p22.3-p24.1 in a consanguineous Pakistani family.
aNational Centre of Excellence in Molecular Biology, University of the Punjab, Lahore Pakistan
bOphthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland
Inquiries to Sheikh Riazuddin, National Centre of Excellence in Molecular Biology, 87 West Canal Bank Road, Lahore 53700, Pakistan
ABSTRACT