Correlation between Karyotype and Phenotype in Turner Syndrome

ABSTRACT

PURPOSE: In spite of the karyotype and phenotype diversity in Turner syndrome patients, there are few reports about such differences in Korea. We reviewed the data of chromosome abnormalities, clinical manifestations, and comorbidities of Turner syndrome patients in Kyungpook National University Hospital to compare them to the recent hypotheses about sex chromosome gene loci related to Turner symptoms. MATERIALS AND METHODS: We identified the cytologic findings of 92 patients with Turner syndrome and the clinical findings of 62 patients among them. RESULTS: 54.3 percent of patients had 45,X while 45.7 percent showed other karyotype combinations (45,X/46,XX, 45,X/46,XX/47,XXX, 46,X,del(Xp), 46,X,del(Xq), 45,X/46,X,del(Xq), 46,X,i(Xq), 45,X/46,X,i (Xq)). The Turner symptoms found included short neck, high arched palate, broad chest, Madelung deformity, short metacarpals, scoliosis, cubitus valgus, low hair line, webbed neck, edematous extremities, pigmented nevus, and sexual infantilism. The specific diseases associated Turner syndrome included renal abnormalities, congenital heart disease, hearing defects, diabetes mellitus, hyperlipidemia, and decreased bone density. The phenotype of the mosaicism group was milder than that of the monosomy group. In the case of 46,X,del(Xp) and 45,X/46,X,del(Xq) groups, all had skeletal abnormalities, but the 46,X,del(Xq) group had none. In the case of 46,X,del(Xp) group, all showed short statures and skeletal abnormalities, but no sexual infantilism was observed. In the case of 46,X,i(Xq) and 45,X/46,X,i(Xq) groups, they all showed delayed puberty and had primary amenorrhea. CONCLUSION: It is important to study karyotype-phenotype correlations in patients with Turner syndrome to obtain interesting information about the genotype-phenotype correlations related to the X chromosome.