title: Segregation patterns and phenotypes of unbalanced offspring in a large family with (10;18) chromosome translocation.
abstract: We describe a large family in whom a balanced 10;18 chromosome translocation is segregating through five generations. Six severely mentally retarded relatives and an abnormal fetus further define the phenotypic expression of dup (18q21----qter). Other segregants detected prenatally included a fetus with deletion 18q21----qter and two fetuses with dup(18pter----q21) owing to tertiary trisomy. One of the latter also had an extra X chromosome; this might be another example of possible nonhomologous pairing in man.
mesh_terms: D002869:Chromosome Aberrations / Q000175:diagnosis / Q000196:embryology / Q000235:genetics*; D025063:Chromosome Disorders; D002902:Chromosomes, Human, 16-18; D002906:Chromosomes, Human, 6-12 and X; D005260:Female; D006580:Genetic Carrier Screening; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D007621:Karyotyping; D008297:Male; D008540:Meiosis; D009630:Nondisjunction, Genetic; D010641:Phenotype; D011296:Prenatal Diagnosis; D014178:Translocation, Genetic