ABSTRACT
Objective To analyze the clinical manifestations and possible gene mutation sites of Chinese patients in order to improve the clinician's understanding of CHARGE syndrome. Methods Clinical data were collected and blood samples were obtained from the proband of CHARGE syndrome and their relatives. The peripheral blood DNA was extracted and sequenced by PCR amplification. Mutation sites were verified by Sanger sequencing. Results For the first proband, a heterozygous mutation was detected in the intron 10 of CHD7 gene. His parents and brother did not have mutation. For the second proband, total repeat sequence in exon 7 of CHD7 gene was detected. His father carried the same mutation and his mother did not have mutation. Conclusion For the patients who are diagnosed with CHARGE syndrome based on the clinical manifestations, genetic mutation detection should be proceeded. It is useful for studying possible genetic pathogenesis and enhancing the awareness of clinicians.
ABSTRACT
CHARGE syndrome is a congenital malformation disorder that includes Coloboma, Heart defect, Atresia of the choanae, Retarded growth and development, Genital hypoplasia, and Ear abnormalities. Recently hypogonadotropic hypogonadism and abnormal olfactory bulb development are occasionally described in CHARGE syndrome with chromodomain helicase DNA-binding protein 7 (CHD7) gene mutation. We report the case of Korean female patient with CHARGE syndrome and CHD7 mutation who had hypogonadotropic hypogonadism and abnormal olfactory bulb as manifested by delayed puberty and growth retardation at 13 years of age. She had both optic nerve coloboma, external ear abnormalities and bilateral agenesis of the semicircular canals. She had severe mental retardation and autistic-like behavior. We identified a heterozygous nonsense mutation at exon 20 of the CHD7 gene (c.4601G>A; Trp1534X).