Recurrence risks for Down syndrome.
The recurrence risks for Down syndrome due to an inherited translocation are estimated from empirical data in the literature for two maternal age groups: mothers under 30 and mothers 30 and over. These risks were found to be approximately 0.3% and 0.05%, respectively. The probability for two Down syndrome sibs both having an inherited translocation was estimated as about 18.2% for the former age group and 2.7% for the latter. The relative effectiveness in preventing. Down syndrome births by karyotyping affected children is discussed.
D002877:Chromosomes, Human / Q000648:ultrastructure; D004314:Down Syndrome / Q000235:genetics* / Q000517:prevention & control; D005260:Female; D005817:Genetic Counseling; D006801:Humans; D007621:Karyotyping; D008297:Male; D008423:Maternal Age; D008957:Models, Genetic; D011336:Probability; D012306:Risk; D014178:Translocation, Genetic