Abstract
The incurable neurodegenerative disorder, Huntington's disease (HD), is caused by an expanded, unstable CAG repeat encoding a stretch of polyglutamine in a 4p16.3 gene (HD) of unknown function. Near the CAG repeat is a polyproline-encoding CCG repeat that shows more limited allelic variation. The mouse homologue, Hdh, has been mapped to chromosome 5, in a region devoid of mutations causing any comparable phenotype. We have isolated overlapping cDNAs from the Hdh gene and compared their sequences with the human transcript. The consensus mouse coding sequence is 86% identical to the human at the DNA level and 91% identical at the protein level. Despite the overall high level of conservation, Hdh possesses an imperfect CAG repeat encoding only seven consecutive glutamines, compared to the 13-36 residues that are normal in man. Although no evidence for polymorphic variation of the CAG repeat was seen, a nearby CCG repeat differed in length by one unit between several strains of laboratory mouse and Mus spretus. The absence of a long CAG repeat in the mouse is consistent with the lack of a spontaneous mouse model of HD. The information presented concerning the sequence of the mouse gene should facilitate attempts to create such a model.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.