title: Trisomy 18 in sibs and maternal chromosome 9 variant.
mesh_terms: D002869:Chromosome Aberrations; D002871:Chromosome Banding; D002877:Chromosomes, Human / Q000648:ultrastructure; D002902:Chromosomes, Human, 16-18; D002906:Chromosomes, Human, 6-12 and X; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007231:Infant, Newborn; D007621:Karyotyping; D010375:Pedigree; D014314:Trisomy