Unequal mitotic sister chromatid exchange and different length of Y chromosomes.
There is wide variation in the length of the Y chromosome. In the same individual the length varies continuously and is normally distributed. We describe a boy with borderline mental retardation, gross and fine motor coordination difficulty, muscle rigidity, ptosis, clinodactyly, and a Y chromosome of different lengths in two separate cell populations. The most probable explanation of the cytogenetic finding is a mitotic unequal sister chromatid exchange of the Y chromosome.
D000293:Adolescent; D000328:Adult; D005260:Female; D005347:Fibroblasts / Q000648:ultrastructure; D005819:Genetic Markers; D006801:Humans; D007621:Karyotyping; D008214:Lymphocytes / Q000648:ultrastructure; D008297:Male; D008938:Mitosis; D010641:Phenotype; D012729:Sex Chromosome Aberrations / Q000235:genetics*; D012854:Sister Chromatid Exchange; D013577:Syndrome; D014998:Y Chromosome / Q000648:ultrastructure*
D005819:Genetic Markers