1. A subtelocentric chromosome 9 in a dysplastic 18-year-old boy with dissociated mental development
- Author
-
Ingo Hansmann and J. Keute
- Subjects
Mental development ,Genetics ,Chromosome Aberrations ,Chromosomes, Human, 6-12 and X ,Male ,0303 health sciences ,Adolescent ,030305 genetics & heredity ,Chromosome ,Chromosome 9 ,Biology ,Human genetics ,03 medical and health sciences ,Chromosome Inversion ,Humans ,Chromosome breakage ,10. No inequality ,Genetics (clinical) ,030304 developmental biology - Abstract
A subtelocentric C-group chromosome was identified as inv(9) (p24q12) in an 18-year-old young man who shows few dysplastic signs and who suffers from dissociated mental development. Pericentric inversions producing an almost metacentric No. 9 have been reported in several studies. The frequency of which proved to be high. There is an apparent lack, however, of inverted acro- or subtelocentric No. 9 reported in the literature. This obvious difference in the break points on chromosome 9 is most likely due to 1. hot-spots for chromosome breakage i.e. highly susceptible regions such as the euchromatic-heterochromatic junctions. 2. a higher degree of elimination against such acro- or subtelocentric chromosomes from one generation to the other.
- Published
- 1975