Choroideremia is linked to the restriction fragment length polymorphism DXYS1 at XQ13-21.
Choroideremia (McK30310), an X-linked hereditary retinal dystrophy, causes night-blindness, progressive peripheral visual field loss, and, ultimately, central blindness in affected males. The location of choroideremia on the X chromosome is unknown. We have used restriction fragment length polymorphisms from the X chromosome to determine the regional localization of choroideremia by linkage analysis in families with this disease. One such polymorphic locus, DXYS1, located on the long arm (Xq) within bands q13-q21, shows no recombination with choroideremia at lod = 5.78. Therefore, with 90% probability, choroideremia maps within 9 centiMorgans (cM) of DXYS1. Another polymorphic locus, DXS11, located within Xq24-q26, also shows no recombination with choroideremia, although at a smaller lod score of 1.54 (90% probability limit theta less than 30 cM). This linkage with DXS11, a marker that is distal to DXYS1, suggests that the locus for choroideremia is also distal to DXYS1 and lies between these two markers in the region Xq13-q24. These results provide regional mapping for the disease that may be useful for prenatal diagnosis and, perhaps ultimately, for isolating the gene locus for choroideremia.
Nussbaum
R L
RL
Lewis
R A
RA
Lesko
J G
JG
Ferrell
R
R
D002829:Choroid; D002874:Chromosome Mapping; D004262:DNA Restriction Enzymes; D005260:Female; D008040:Genetic Linkage; D005819:Genetic Markers; D006801:Humans; D008126:Lod Score; D008297:Male; D010375:Pedigree; D011110:Polymorphism, Genetic; D012162:Retinal Degeneration / Q000235:genetics*; D014603:Uveal Diseases / Q000235:genetics; D014960:X Chromosome
D005819:Genetic Markers; D004262:DNA Restriction Enzymes