Investigation of the origins of human autosomal inversions |
| |
Authors: | N Simon Thomas Victoria Bryant Vivienne Maloney Annette E Cockwell Patricia A Jacobs |
| |
Institution: | (1) Wessex Regional Genetics Laboratory, Salisbury NHS Foundation Trust, Salisbury District Hospital, Salisbury, SP2 8BJ, UK;(2) Department of Human Genetics, University of Southampton, Southampton, UK;(3) National Genetics Reference Laboratory (Wessex), Salisbury District Hospital, Salisbury, SP2 8BJ, UK |
| |
Abstract: | A significant proportion of both pericentric and paracentric inversions have recurrent breakpoints and so could either have
arisen through multiple independent events or be identical by descent (IBD) with a single common ancestor. Of two common variant
inversions previously studied, the inv(2)(p11q13) was genuinely recurrent while the inv(10)(p11.2q21.2) was IBD in all cases
tested. Excluding these two variants we have ascertained 257 autosomal inversion probands at the Wessex Regional Genetics
Laboratory. There were 104 apparently recurrent inversions, representing 35 different breakpoint combinations and we speculated
that at least some of these had arisen on more than one occasion. However, haplotype analysis identified no recurrent cases
among eight inversions tested, including the variant inv(5)(p13q13). The cases not IBD were shown to have different breakpoints
at the molecular cytogenetic level. No crossing over was detected within any of the inversions and the founder haplotypes
extended for variable distances beyond the inversion breakpoints. Defining breakpoint intervals by FISH mapping identified
no obvious predisposing elements in the DNA sequence. In summary the vast majority of human inversions arise as unique events.
Even apparently recurrent inversions, with the exception of the inv(2)(p12q13), are likely to be either derived from a common
ancestor or to have subtly different breakpoints. Presumably the lack of selection against most inversions allows them to
accumulate and disperse amongst different populations over time.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. |
| |
Keywords: | |
本文献已被 PubMed SpringerLink 等数据库收录! |
|