A 5.3Mb deletion in chromosome 18q12.3 as the smallest region of overlap in two patients with expressive speech delay

摘要: Interstitial 18q deletions encompassing band 18q12.3 define the del(18)(q12.2q21.1) syndrome. Usual manifestations are mild dysmorphic features, mental retardation, behaviour abnormalities and lack of serious malformation. Seizures have also been found. Recently, more specifically, impairment expressive language has reported. We report on two patients with de novo interstitial characterized by oligonucleotide array CGH. The smallest, a 5.3Mb deletion (35.7-40.9Mb) within q12.3, was found in 4-year-old girl who suffered mainly from dysphasia. A larger 9.5Mb (34.6-43.9Mb) observed 20-year-old man severe clinical picture including seizures limited speech. Among four genes located region, RIT2 (Ras-like without CAAX 2) SYT4 (synaptotagmin IV), both strongly expressed brain, pointed out as likely candidate for development.