Zinc finger 81 (ZNF81) mutations associated with X-linked mental retardation

We have cloned the breakpoints of a de novo translocation t( X; 9)( p11.23; q34.3) in a mentally retarded female. The translocation disrupts the gene ZNF81 on the X chromosome. ZNF81 is highly homologous to ZNF41, another zinc finger gene associated with non-specific X-linked mental retardation. Mutation analysis in more than 300 families and patients with non-specific X-linked mental retardation revealed a sequence change p. S179N in MRX45, fully segregating with the phenotype. It is likely that ZNF81 represents a novel MRX gene which is causally involved in a minority of patients with non-specific X-linked mental retardation.