A gene (SRPX) encoding a sushi-repeat-containing protein is deleted in patients with X-linked retinitis pigmentosa.
X-linked retinitis pigmentosa (XLRP) is characterized by retinal degeneration with night blindness and progressive reduction of the visual fields. By linkage and deletion analysis a gene locus (RP3) has been mapped to the short arm of the X chromosome between the genes CYBB and OTC. Analysis of transcript in this region has revealed a gene which is abundantly expressed in human retina and encodes a putative membrane protein with significant homologies to short consensus repeat (SCR/sushi) domains known from selections and complement proteins. The gene termed SRPX (sushi-repeat-containing protein, x chromosome) is deleted in an RP patient who also suffers from chronic granulomatous disease and McLeod syndrome. A 75 kb deletion removing exon 1 of the gene was also found in two brothers of a second XLRP family. However, no further functionally significant mutations were detected by SSCP screening of all 10 exons in 34 unrelated XLRP patients nor by full length RT-PCR sequencing in two RP3 families. The role of this highly conserved retinal gene in the pathogenesis of RP therefore remains to be determined.
Meindl
A
A
Abteilung Padiatrische Genetik, Kinderpoliklik der Ludwig-Maximilians- Unversitat Munchen.
Carvalho
M R
MR
Herrmann
K
K
Lorenz
B
B
Achatz
H
H
Lorenz
B
B
Apfelstedt-Sylla
E
E
Wittwer
B
B
Ross
M
M
Meitinger
T
T
D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D003001:Cloning, Molecular; D018076:DNA, Complementary; D005260:Female; D017353:Gene Deletion; D006801:Humans; D008297:Male; D008565:Membrane Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D051381:Rats; D015183:Restriction Mapping; D012160:Retina / Q000378:metabolism; D012174:Retinitis Pigmentosa / Q000235:genetics*; D014960:X Chromosome
D018076:DNA, Complementary; D008565:Membrane Proteins; C486297:SRPX protein, human; C099179:Srpx protein, rat