Partial trisomy for5qandmonosomyfor12pin aliveborn child asaresult ofacomplex five breakpoint chromosome rearrangement ina parent

A balancedcomplexchromosomerearrangement (CCR)involving fourchromosomesisveryrareandmay leadto different typesofaneuploid germ cells. We reportaliveborn child withmultiple congenital anomalies andanapparently balancedtranslocation, t(11;12). High resolution chromosomeanalysis inthe mothershoweda CCR involving chromosomes 5,11,12,and 16.In situ hybridisation showedthatthisCCR was theresult ofafivebreakrearrangement, andthatthederivative chromosome12 consisted ofpartsofchromosomes5,11, and12.Fromthisitcouldbededucedthat thekaryotype of the childwas not balanced, butresulted inpartial trisomy forSqandpartial monosomyfor12p.The clinical findings inthechildwerecompatible withpartial trisomy for5q. (JMedGenet1992;29:739-41)