期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1998
卷号:95
期号:2
页码:719-724
DOI:10.1073/pnas.95.2.719
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:There have been several claims of segregation distortion (meiotic drive) for loci associated with diseases caused by trinucleotide repeats, leading us to test for this phenomenon in a large study of the X-linked loci FRAXA and FRAXE. We found no evidence of meiotic drive in females and no convincing evidence in males, where the limitation of risk to daughters creates a testing bias for alleles of interest. Alleles for pre- and full mutation, intermediate alleles, and common alleles were analyzed separately, with the same negative results that are extended in the discussion to claims of meiotic drive for other diseases. On the other hand, an excess risk of learning difficulties was confirmed for intermediate FRAXA alleles (relative risk, 2.58 {+/-} .74) and suggested for intermediate FRAXE alleles. The penetrance of learning difficulty is low, the risk being estimated as .039 for FRAXA common alleles and .101 for intermediate alleles. Because of their lower gene frequency, full mutations are a less frequent cause of learning difficulty than intermediate alleles, which contribute .0020 to total prevalence and .0012 to attributable prevalence of learning difficulty.