A girl with partial trisomy 12q24.31 inherited from her father and a possible novel syndrome transmitted from her mother.

We report on a familial partial trisomy 12q in a girl and her father both of whom have an unbalanced translocation, der(16)t(12;16)(q24.31;q24.3), resulting in trisomy 12q24.31 --> qter and 16q subtelomere deletion. By comparing phenotypes of the girl and the father, we suggest that clinical features related to trisomy 12q24.31 --> qter are mild development delays, mild mental retardation, broad forehead, simplified ear helices, small mouth, and thin lips. The mother who has a normal karyotype has moderate mental retardation and a facial appearance similar to the girl. Both the girl and the mother have distinctive short, curly, and kinky hair. We suspect a possible new syndrome in the maternal family with mental retardation and curly, kinky hair. Thus, this patient likely inherited two discreet conditions causing mental retardation.