Leukaemia and transient leukaemia in Down syndrome.
We have reviewed 215 published cases of leukaemia and transient leukaemia in Down syndrome. There is an over-representation of mosaic trisomy 21, possibly the result, at least in part, of a survival effect. The most intriguing observation is a bimodal distribution of maternal age, produced largely because cases with true leukaemia have a significantly higher maternal age than cases with transient leukaemia (33.5 versus 29.5 years). In conjunction with evidence that meiosis I nondisjunction is infrequent in transient leukaemia, this suggests different mechanisms for the etiology of leukaemia and transient leukaemia, and favours a locus predisposing to transient leukaemia proximal to the centromere on the long arm of chromosome 21.
Iselius
L
L
CRC Research Group in Genetic Epidemiology, Department of Community Medicine, Southampton General Hospital, UK.
Jacobs
P
P
Morton
N
N
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D002891:Chromosomes, Human, Pair 21; D004314:Down Syndrome / Q000150:complications* / Q000235:genetics; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007621:Karyotyping; D007938:Leukemia / Q000145:classification / Q000150:complications / Q000235:genetics*; D008297:Male; D008423:Maternal Age; D012307:Risk Factors; D012744:Sex Ratio