A 785 kb deletion of 3p14.1p13, including the FOXP1 gene, associated with speech delay, contractures, hypertonia and blepharophimosis

We report a child with a 785 kb deletion of the 3p14.1p13 region including the genes FOXP1, EIF4E3, PROK2, GPR27 resulting in speech delay, contractures, hypertonia and blepharophimosis. FOXP1 and FOXP2 are transcription factors containing a polyglutamine tract and a forkhead DNA binding domain. They both play a role in the developing human foregut and brain [W. Shu, M.M. Lu, Y. Zhang, P. Tucker, D. Zhou, E.E. Morrisey, Foxp2 and Foxp1 cooperatively regulate lung and esophagus development, Development 134 (2007) 1991–2000, E. Spiteri, G. Konopka, G. Coppola, J. Bomar, M. Oldham, J. Ou, et al. Identification of the transcriptional targets of FOXP2, a gene linked to speech and language, in developing human brain, Am. J. Hum. Genet. 81 (2007) 1144–1157, S. Tamura, Y. Morikawa, H. Iwanishi, T. Hisaoka, E. Senba. Expression pattern of the winged-helix/forkhead transcription factor Foxp1 in the developing central nervous system, Gene Expr. Patterns. 3 (2003) 193–197.]. Mutations in FOXP2 are known to cause severe speech and language abnormalities [C.S.L. Lai, S.E. Fisher, J.A. Hurst, F. Vargha-Khadem, A.P. Monaco, A forkhead-domain gene is mutated in a severe speech and language disorder, Nature 413 (2001) 519–523.] in humans and animals. It has been suggested that overlap of FOXP1 and FOXP2 expression in the songbird and human brain may indicate that mutations in FOXP1 would also result in speech and language abnormalities. The roles of EIF4E3, PROK2 and GPR27 are also evaluated.