Molecular genetics of human blue cone monochromacy.
Blue cone monochromacy is a rare X-linked disorder of color vision characterized by the absence of both red and green cone sensitivities. In 12 of 12 families carrying this trait, alterations are observed in the red and green visual pigment gene cluster. The alterations fall into two classes. One class arose from the wild type by a two-step pathway consisting of unequal homologous recombination and point mutation. The second class arose by nonhomologous deletion of genomic DNA adjacent to the red and green pigment gene cluster. These deletions define a 579-base pair region that is located 4 kilobases upstream of the red pigment gene and 43 kilobases upstream of the nearest green pigment gene; this 579-base pair region is essential for the activity of both pigment genes.
Nathans
J
J
Department of Molecular Biology and Genetics, Wilmer Ophthalmologic Institute, Johns Hopkins University School of Medicine, Baltimore, MD 21205.
Davenport
C M
CM
Maumenee
I H
IH
Lewis
R A
RA
Hejtmancik
J F
JF
Litt
M
M
Lovrien
E
E
Weleber
R
R
Bachynski
B
B
Zwas
F
F
D000293:Adolescent; D000328:Adult; D001483:Base Sequence; D002648:Child; D002675:Child, Preschool; D002872:Chromosome Deletion; D003117:Color Vision Defects / Q000235:genetics*; D004247:DNA / Q000032:analysis; D005260:Female; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D009154:Mutation; D009693:Nucleic Acid Hybridization; D012168:Retinal Pigments / Q000235:genetics; D013789:Thalassemia / Q000235:genetics; D014960:X Chromosome
D012168:Retinal Pigments; D004247:DNA