Publication Date:
1988-06-17
Description:
Unequal crossing-over within a head-to-tail tandem array of the homologous red and green visual pigment genes has been proposed to explain the observed variation in green-pigment gene number among individuals and the prevalence of red-green fusion genes among color-blind subjects. This model was tested by probing the structure of the red and green pigment loci with long-range physical mapping techniques. The loci were found to constitute a gene array with an approximately 39-kilobase repeat length. The position of the red pigment gene at the 5' edge of the array explains its lack of variation in copy number. Restriction maps of the array in four individuals who differ in gene number are consistent with a head-to-tail configuration of the genes. These results provide physical evidence in support of the model and help to explain the high incidence of color blindness in the human population.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Vollrath, D -- Nathans, J -- Davis, R W -- GM21891/GM/NIGMS NIH HHS/ -- New York, N.Y. -- Science. 1988 Jun 17;240(4859):1669-72.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biochemistry, Stanford University School of Medicine, CA 94305.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/2837827" target="_blank"〉PubMed〈/a〉
Keywords:
Color Vision Defects/*genetics
;
Crossing Over, Genetic
;
DNA/genetics
;
DNA Restriction Enzymes
;
Electrophoresis, Agar Gel
;
Exons
;
Female
;
Genetic Variation
;
Humans
;
Male
;
Nucleic Acid Hybridization
;
Recombination, Genetic
;
Repetitive Sequences, Nucleic Acid
;
Retinal Pigments/*genetics
;
*X Chromosome
Print ISSN:
0036-8075
Electronic ISSN:
1095-9203
Topics:
Biology
,
Chemistry and Pharmacology
,
Computer Science
,
Medicine
,
Natural Sciences in General
,
Physics
