Maternal origin of a de novo balanced t(21q21q) identified by ets-2 polymorphism

Abstract

Molecular investigations were done in a woman with a de novo balanced t(21q21q) discovered because of the birth of a trisomic 21 baby. Polymorphisms detected with probe ets-2 after Msp I digestion showed that both chromosomes 21 involved in the rearrangement were of maternal origin. The most likely hypothesis is that of a disomic 21 oocyte fertilized by a nullisomic 21 sperm.

Homologous Robertsonian translocation (21q21q) and abortions

“…Forssman and Lehmann (1962) and Dallaire and Fraser (1964) reported the occurrence of t(21q21q) in the male partners of couples with recurrent abortions and in their offspring with Down's syndrome, as observed in couple RA1 of the present study. Transmission of t(21q21q) from a mother to her offspring, as seen in the other couple (RA81), has been reported by various investigators (Hamerton et al 1961;Furbetta et al 1973;Creau-Goldberg et al 1987). Pulliam and Huether (1986), in an epidemiologic and cytogenetic study of translocations in Down's syndrome children in Ohio, recorded an incidence of translocations in 5.2% of 688 Down's syndrome live births.…”

“…However, Creau-Goldberg et al (1987) employed D N A probes to examine the origin of a de novo balanced t(21q21q) and found it to be maternal. They suggested that the fertilization of a disomic 21 oocyte having t(21q21q) by a nullisomic 21 sperm leads to a diploid complement of 45 chromosomes in the carriers.…”

Uniparental disomy (UPD) other than 15: Phenotypes and bibliography updated

“…The first case was described by Créau-Goldberg et al [1987]. This case was also one of the first cases of UPD at all.…”

A fascination with chromosome rescue in uniparental disomy: Mendelian recessive outlaws and imprinting copyrights infringements

“…Detecting UPD21 with present means will thus remain quite hard, except in cases where an isochromosome 21, de novo or transmitted, calls attention to it. 9 A different pattern of conversion to UPD is seen for other chromosome members of somewhat different pathologic behaviour. Our review of the situation in UPD1, maternal or paternal, emphasizes again the major role of maternal meiosis errors.…”