nondisjunction

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nondisjunction

[¦nän′dis‚jaŋk·shən]
(genetics)
Failure of homologous chromosomes to separate symmetrically during cell division, with both ending up in the same daughter cell instead of in each daughter cell.
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DS with DS with DS with type hypothyroidism celiac 1 DM disease n 18 1 4 Percentage 19.6 1.1 4.3 Chromosomal 1 mosaic, 17 non- 1 non- 4 non- abnormality disjunction disjunction disjunction Male 9 1 2 Female 9 0 2 BMI 4 overweight * and 1 normal 1 obese ** out 3 obese ** out of 11 of 3 DS with two DS with three Total autoimmune autoimmune diseases diseases n 1 0 22 Percentage 1.1 0.0 23.9 Chromosomal 1 mosaic, 21 abnormality non-disjunction Male 1 0 11 Female 0 0 10 BMI 1 obese ** 0 4 overweight * and 3 obese ** * Overweight are those whose body mass indexs (BMIs) were > 90th percentile (equivalent to BMI > 25 in adults).
The chromosomal non-disjunction was the most common type of chromosomal abnormality in Down syndrome.
Distribution of Karyotyping Karyotyping Frequency Percentage Non-disjunction 94 74.6 Translocation 5 4 Not done 27 21.4 Total 126 100 Table 7.
1976) and caused chromosomal non-disjunction effects (Ramel 1973).
Given that there is little detailed information on the architecture of chromatin associated to DSCR, in this study, through an extensive biotechnology analysis, a series of co-genomic variables were evaluated, permitting the characterization of the topological state of the critical regions associated to DS that would be implicated in processes of non-disjunction and in epigenetic events.
Secondly, the two versions of each exercise allow for detecting different non-disjunction events in the F1 progeny of the cross that generates the dihybrid or trihybrid females for test-crossing.
The majority of cases (80%) are caused by the presence of an additional chromosome 13 owing to non-disjunction (usually in maternal meiosis I); ~10-20% are due to translocations, usually an unbalanced 13:14 Robertsonian translocation.
The main cause of deterioration of oocyte quality is meiotic non-disjunction (20).

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