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Trisomy 21: Origin of non-disjunction

✍ Scribed by J. Mazo; Amalia Pérez Castillo; J. A. Abrisqueta


Publisher
Springer
Year
1982
Tongue
English
Weight
379 KB
Volume
62
Category
Article
ISSN
0340-6717

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✦ Synopsis


The Q-band heteromorphisms of chromosome 21 were used in a sample of 48 families with a Down's syndrome child to evaluate the origin of non-disjunction. The parental origin and the meiotic error were determined in 27 families, and in eight families only partial information was obtained. Paternal and maternal origin of non-disjunction was in a 1:3 ratio. Failures were five times more frequent in first than in second meiotic division in both sexes. The mean parental age and environmental factors in relation to the origin of the anomaly are discussed. Our results are compared with those obtained previously in similar studies by other authors.


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