Ring Chromosome 18: A Case Report

Document Type : Case Report

Authors
Shermineh Heydari
Fahimeh Hassanzadeh
Mohammad Hassanzadeh Nazarabadi
Department of Medical Genetics, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
Abstract
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.
Keywords
Ring chromosome 18
karyotyping
mental retardation