[Retinitis pigmentosa: results of rhodopsin gene analysis in the Galician population].
OBJECTIVE
Retinitis pigmentosa (RP) is the most prevalent inherited degeneration in the retina. The clinical manifestations are variable in terms of severity, age of onset and progression. The clinical variation is paralleled by genetic heterogeneity (more than 20 different loci have been described to date). The aim of this work was to identify mutations in rhodopsin gene and to determine the frequencies of the different genetic forms of RP in the Galician population.


METHODS
47 previously diagnosed RP patients and their relatives were studied. Genetic forms of RP were identified by recording full family history and clinical examination. DNA samples from patients with RP and control individuals were screened for point mutations in the rhodopsin gene by using PCR SSCPs (Single Strand Conformation Polymorphisms) and direct sequencing in 36 unrelated nonsyndromic RP patients.


RESULTS
We report the frequency distribution of the different genetic RP forms. In the SSCPs analysis of rhodopsin gene we found different mobility shifts: one variant in the 5'-untranslated region of the gen and one variant in the third intron. Direct sequencing revealed an A269-->G and an C3982-->T transitions, respectively. Additionally, we observed a single base change in codon 160 (C-->A) of this gene.


CONCLUSIONS
Polymorphisms are commom findings in the exon 1 and 3 of rhodopsin gene. They are neutral variations and do not represent a change in the protein. No significant differences in the frecuencies of A269-->G and C3982-->T polymorphisms among the three groups of RP patients (ADRP, ARRP, Esporadic RP) and normal individuals were found. There was no significant deviation from Hardy-Weinberg's equilibrium in each genotype in any group.
Blanco
M J
MJ
Servicio de Oftalmología, Instituto Gallego de Oftalmología, Instituto de Medicina Legal, Universidad de Santiago de Compostela, España.
Capeans
C
C
Lareu
M V
MV
Carracedo
A
A
Piñero
A
A
Santos
L
L
Copena
M J
MJ
Sánchez-Salorio
M
M
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017354:Point Mutation; D012174:Retinitis Pigmentosa / Q000235:genetics*; D012243:Rhodopsin / Q000235:genetics*; D013030:Spain
D012243:Rhodopsin