Diagnosis of chromosome 3 duplication q23----qter, deletion p25----pter in a patient with the C (trigonocephaly) syndrome.

The cells of a deceased patient previously reported to have the C (trigonocephaly) syndrome were reinvestigated because his phenotype resembled that of a patient with a duplication-deficiency of chromosome 3. This diagnosis was confirmed using fibroblasts grown from frozen cells, and his mother was shown to carry an inversion of chromosome 3 in her peripheral blood leukocytes. His findings are compared to those of another patient with the C trigonocephaly syndrome with normal chromosomes and to others from the literature. At least one other patient from the literature has a phenotype compatible with "3q duplication syndrome."