TY - JOUR
T1 - Mutations in GRM6 identified in consanguineous Pakistani families with congenital stationary night blindness
AU - Naeem, Muhammad Asif
AU - Gottsch, Alexander D.H.
AU - Ullah, Inayat
AU - Khan, Shaheen N.
AU - Husnain, Tayyab
AU - Butt, Nadeem H.
AU - Qazi, Zaheeruddin A.
AU - Akram, Javed
AU - Riazuddin, Sheikh
AU - Ayyagari, Radha
AU - Hejtmancik, J. Fielding
AU - Riazuddin, S. Amer
N1 - Publisher Copyright:
© 2015 Molecular Vision.
PY - 2015/10/31
Y1 - 2015/10/31
N2 - Purpose: This study was undertaken to investigate the causal mutations responsible for autosomal recessive congenital stationary night blindness (CSNB) in consanguineous Pakistani families. Methods: Two consanguineous families with multiple individuals manifesting symptoms of stationary night blindness were recruited. Affected individuals underwent a detailed ophthalmological examination, including fundus examination and electroretinography. Blood samples were collected and genomic DNA was extracted. Exclusion analyses were completed by genotyping closely spaced microsatellite markers, and two-point logarithm of odds (LOD) scores were calculated. All coding exons, along with the exon–intron boundaries of GRM6, were sequenced bidirectionally. Results: According to the medical history available to us, affected individuals in both families had experienced night blindness from the early years of their lives. Fundus photographs of affected individuals in both the families appeared normal, with no signs of attenuated arteries or bone spicule pigmentation. The scotopic electroretinogram (ERG) response were absent in all of the affected individuals, while the photopic measurements show reduced b-waves. During exclusion analyses, both families localized to a region on chromosome 5q that harbors GRM6, a gene previously associated with autosomal recessive CSNB. Bidirectional sequencing of GRM6 identified homozygous single base pair changes, specifically c.1336C>T (p.R446X) and c.2267G>A (p.G756D) in families PKRP170 and PKRP172, respectively. Conclusions: We identified a novel nonsense and a previously reported missense mutation in GRM6 that were responsible for autosomal recessive CSNB in patients of Pakistani decent.
AB - Purpose: This study was undertaken to investigate the causal mutations responsible for autosomal recessive congenital stationary night blindness (CSNB) in consanguineous Pakistani families. Methods: Two consanguineous families with multiple individuals manifesting symptoms of stationary night blindness were recruited. Affected individuals underwent a detailed ophthalmological examination, including fundus examination and electroretinography. Blood samples were collected and genomic DNA was extracted. Exclusion analyses were completed by genotyping closely spaced microsatellite markers, and two-point logarithm of odds (LOD) scores were calculated. All coding exons, along with the exon–intron boundaries of GRM6, were sequenced bidirectionally. Results: According to the medical history available to us, affected individuals in both families had experienced night blindness from the early years of their lives. Fundus photographs of affected individuals in both the families appeared normal, with no signs of attenuated arteries or bone spicule pigmentation. The scotopic electroretinogram (ERG) response were absent in all of the affected individuals, while the photopic measurements show reduced b-waves. During exclusion analyses, both families localized to a region on chromosome 5q that harbors GRM6, a gene previously associated with autosomal recessive CSNB. Bidirectional sequencing of GRM6 identified homozygous single base pair changes, specifically c.1336C>T (p.R446X) and c.2267G>A (p.G756D) in families PKRP170 and PKRP172, respectively. Conclusions: We identified a novel nonsense and a previously reported missense mutation in GRM6 that were responsible for autosomal recessive CSNB in patients of Pakistani decent.
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M3 - Article
C2 - 26628857
AN - SCOPUS:84946913402
SN - 1090-0535
VL - 21
SP - 1261
EP - 1271
JO - Molecular vision
JF - Molecular vision
ER -