A screen for mutations in the transducin gene GNB1 in patients with autosomal dominant retinitis pigmentosa.
OBJECTIVE
To search for mutations in the GNB1 gene (coding for the transducin beta1-subunit protein) in patients with autosomal dominant retinitis pigmentosa.


METHODS
We screened 185 unrelated patients with autosomal dominant retinitis pigmentosa (ADRP) using direct genomic sequencing of the three non-coding exons and 9 coding exons, along with immediately flanking intron DNA.


RESULTS
We found 2 polymorphisms, one in intron 1 with a minor allele frequency of 24%, and one in intron 6 with a minor allele frequency of 12% among the 185 patients. Two rare variants (minor allele frequency <1%) were found in the 3' untranslated region of exon 12. No changes were found in the open reading frame (exons 3-11) or in the noncoding exons 1 and 2.


CONCLUSIONS
No likely pathogenic GNB1 mutations have been found in any of 185 unrelated patients with ADRP. This result would be expected if hemizygosity for GNB1 does not result in ADRP or is a rare cause of ADRP.
Mylvaganam
Geetha H
GH
Ocular Molecular Genetics Institute and the Berman-Gund Laboratory for the Study of Retinal Degenerations, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA 02114, USA.
McGee
Terri L
TL
Berson
Eliot L
EL
Dryja
Thaddeus P
TP
D020413:3' Untranslated Regions; D004252:DNA Mutational Analysis / Q000379:methods; D005091:Exons; D044387:GTP-Binding Protein beta Subunits / Q000235:genetics*; D005787:Gene Frequency; D005799:Genes, Dominant; D014644:Genetic Variation; D006801:Humans; D007438:Introns; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D012174:Retinitis Pigmentosa / Q000235:genetics*
D020413:3' Untranslated Regions; C516790:GNB1 protein, human; D044387:GTP-Binding Protein beta Subunits