TY - JOUR
T1 - Comparative study of microsatellite and cytogenetic markers for detecting the origin of the nondisjoined chromosome 21 in down syndrome
AU - Petersen, Michael B.
AU - Frantzen, Merete
AU - Antonarakis, Stylianos E.
AU - Warren, Andrew C.
AU - Van Broeckhoven, Christine
AU - Chakravarti, Aravinda
AU - Cox, Tara K.
AU - Lund, Connie
AU - Olsen, Bodil
AU - Poulsen, Hanne
AU - Sand, Annie
AU - Tommerup, Niels
AU - Mikkelsen, Margareta
PY - 1992/9
Y1 - 1992/9
N2 - Nondisjunction in trisomy 21 has traditionally been studied by cytogenetic heteromorphisms. Those studies assumed no crossing-over on the short arm of chromosome 21. Recently, increased accuracy of detection of the origin of nondisjunction has been demonstrated by DNA polymorphism analysis. We describe a comparative study of cytogenetic heteromorphisms and seven PCR-based DNA polymorphisms for detecting the origin of the additional chromosome 21 in 68 cases of Down syndrome. The polymorphisms studied were the highly informative microsatellites at loci D21S215, D21S120, D21S192, IFNAR, D21S156, HMG14, and D21S171. The meiotic stage of nondisjunction was assigned on the basis of the pericentromeric markers D21S215, D21S120, and D21S192. Only unequivocal cytogenetic results were compared with the results of the DNA analysis. The parental and meiotic division origin could be determined in 51% of the cases by using the cytogenetic markers and in 88% of the cases by using the DNA markers. Although there were no discrepancies between the two scoring systems regarding parental origin, there were eight discrepancies regarding meiotic stage of nondisjunction. Our results raise the possibility of recombination between the two marker systems, particularly on the short arm.
AB - Nondisjunction in trisomy 21 has traditionally been studied by cytogenetic heteromorphisms. Those studies assumed no crossing-over on the short arm of chromosome 21. Recently, increased accuracy of detection of the origin of nondisjunction has been demonstrated by DNA polymorphism analysis. We describe a comparative study of cytogenetic heteromorphisms and seven PCR-based DNA polymorphisms for detecting the origin of the additional chromosome 21 in 68 cases of Down syndrome. The polymorphisms studied were the highly informative microsatellites at loci D21S215, D21S120, D21S192, IFNAR, D21S156, HMG14, and D21S171. The meiotic stage of nondisjunction was assigned on the basis of the pericentromeric markers D21S215, D21S120, and D21S192. Only unequivocal cytogenetic results were compared with the results of the DNA analysis. The parental and meiotic division origin could be determined in 51% of the cases by using the cytogenetic markers and in 88% of the cases by using the DNA markers. Although there were no discrepancies between the two scoring systems regarding parental origin, there were eight discrepancies regarding meiotic stage of nondisjunction. Our results raise the possibility of recombination between the two marker systems, particularly on the short arm.
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M3 - Review article
C2 - 1386710
AN - SCOPUS:0026785123
SN - 0002-9297
VL - 51
SP - 516
EP - 525
JO - American journal of human genetics
JF - American journal of human genetics
IS - 3
ER -