The lymphocyte chromosomes of trisomy 21 Down syndrome patients and their parents in a random series of 374 families were analyzed, the objective being the identification of parental mosaicism. The numbers of parents in whom at least two trisomy 21 cells were detected were seven mothers and three fa
Trisomy 21 Down syndrome
β Scribed by Irene A. Uchida; C. P. Freeman
- Publisher
- Springer
- Year
- 1986
- Tongue
- English
- Weight
- 984 KB
- Volume
- 72
- Category
- Article
- ISSN
- 0340-6717
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β¦ Synopsis
In a series of 374 families with Down syndrome progeny, structural chromosome rearrangements were detected in the parents of six children with regular trisomy. The aberrations were reciprocal translocations and inversions. In all three informative families, the parent who transmitted the extra chromosome was not the one with the structural rearrangement. Among the three non-informative families there was one in which both parents carried different reciprocal translocations. In two other families a chromosome aberration was detected: a triple X mother and a father with a Philadelphia chromosome. Omitting the four parents with possible biased ascertainment, 0.4% had a chromosome rearrangement. When the parents with constitutional chromosome aberrations and those with mosaicism, described previously, are combined, the frequency of chromosomally abnormal parents lies between 1.9% and 3.2%. When correlated with parental transmission of the extra chromosome, mosaicism rather than structural rearrangements appears to be of etiologic significance.
π SIMILAR VOLUMES
A hypothesis relating interferon action and the chromosome 21 trisomy genotype and phenotype was presented in this journal in 1980. Since that time a number of additional genes involved in interferon action have been mapped to the distal Down Syndrome region of chromosome 21 and a growing literature