Heydari Shermineh, Hassanzadeh Fahimeh, Hassanzadeh Nazarabadi Mohammad
Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran.
Int J Mol Cell Med. 2014 Fall;3(4):287-9.
Ring chromosomes are rare chromosomal disorders that usually appear to occur de novo. A ring chromosome forms when due to deletion both ends of chromosome fuse with each other. Depending on the amount of chromosomal deletion, the clinical manifestations may be different. So, ring 18 syndrome is characterized by severe mental growth retardation as well as microcephaly, brain and ocular malformations, hypotonia and other skeletal abnormalities. Here we report a 2.5 years old patient with a cleft lip, club foot, mental retardation and cryptorchidism. Chromosomal analysis on the basis of G-banding technique was performed following patient referral to the cytogenetic laboratory. Chromosomal investigation appeared as 46, XY, r(18) (p11.32 q21.32). According to the clinical features of such patients, chromosome investigation is strongly recommended.
环状染色体是罕见的染色体疾病，通常似乎是新发的。当染色体的两端由于缺失而相互融合时，就会形成环状染色体。根据染色体缺失的量不同，临床表现可能会有所不同。因此，18号环状染色体综合征的特征是严重的智力发育迟缓以及小头畸形、脑和眼部畸形、肌张力低下和其他骨骼异常。我们在此报告一名2.5岁患有唇裂、马蹄内翻足、智力发育迟缓及隐睾症的患者。患者转诊至细胞遗传学实验室后，基于G显带技术进行了染色体分析。染色体检查结果显示为46, XY, r(18) (p11.32 q21.32)。根据这类患者的临床特征，强烈建议进行染色体检查。
