Array comparative genomic hybridization analysis of a familial duplication of chromosome 13q: a recognizable syndrome.

We report on a family with six persons in three generations who have mild mental retardation, behavioral problems, seizures, hearing loss, strabismus, dental anomalies, hypermobility, juvenile hallux valgus, and mild dysmorphic features. Classical cytogenetic analysis showed a partial duplication of chromosome 13q, array comparative genomic hybridization showed the duplication to span approximately 21 Mb, ranging from chromosome band 13q21.31 to 13q31.1. The relatively mild presentation of this large duplication may be explained by the relative paucity of genes in the chromosome region involved. Genotype-phenotype correlations in patients with similar partial 13q duplications are inconsistent. Emerging cytogenetic techniques will allow more reliable genotype-phenotype correlations.