title: Two sibs with duplication of 4q31-->qter due to 3:1 meiotic disjunction and mild phenotype.
abstract: Two sibs with duplication of 4q31-->qter due to 3:1 meiotic disjunction and mild phenotype: Clinical and cytogenetic findings in two sibs with partial duplication of 4q31.3-->qter and 21q11.2-->pter are reported. These patients are rare cases of reoccurrence of those partial trisomies due to 3:1 segregation of a maternal balanced translocation. A review of the literature reporting cases of trisomy of the 4q31-->qter segment is also made; previously reported cases mostly in addition have deletions of other chromosomes resulting from adjacent segregation of balanced translocation. The findings of our study confirm the high risk for offspring with unbalanced rearrangements in women with reciprocal translocation involving acrocentric and short chromosome segments. The study also points out that duplication of 4q31-->qter may go along with only mild phenotypic findings if there is no significant additional aneuploidy of the other chromosome involved in the rearrangement.
authors.affiliation: Human Genetics and Cytogenetics Laboratory, Instituto de Biologia, Universidade Federal da Bahia, Salvador, Bahia, Brazil.
authors.forename: L M
authors.initials: LM
authors.lastname: Moreira
authors.forename: M
authors.initials: M
authors.lastname: Riegel
mesh_terms: D002891:Chromosomes, Human, Pair 21 / Q000235:genetics; D002894:Chromosomes, Human, Pair 4 / Q000235:genetics*; D005260:Female; D020440:Gene Duplication; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008540:Meiosis / Q000235:genetics; D010375:Pedigree; D010641:Phenotype; D014314:Trisomy / Q000235:genetics*