Clinical phenotype and genetic analysis of twelve children with ring chromosomes / 中华医学遗传学杂志

OBJECTIVE@#To explore the prevalence and clinical manifestations of ring chromosomes among children featuring abnormal development.@*METHODS@#From January 2015 to August 2021, 7574 children referred for abnormal development were selected, and their peripheral blood samples were subjected to G-banded chromosomal karyotyping analysis.@*RESULTS@#Twelve cases of ring chromosomes were detected, which have yielded a prevalence of 0.16% and included 1 r(6), 2 r(9), 1 r(13), 1 r(14), 2 r(15), 1 r(21) and 3 r(X). The children had various clinical manifestations including growth and mental retardation, limb malformation, and congenital heart disease. For two children with r(9) and two with r(15) with similar breakpoints, one child with r(9) and one with r(15) only had growth retardation, whilst another with r(9) and another with r(15) also had peculiar facies and complex congenital heart disease. The r(X) has featured some manifestations of Turner syndrome.@*CONCLUSION@#Ring chromosomes are among the common causes for severe growth and mental retardation in children with diverse clinical phenotypes. Clinicians should pay attention to those with developmental anomalies and use chromosomal analysis to elucidate their genetic etiology.

Cytogenetic analysis on 5329 children in genetic counseling / 实用医学杂志

Objective To explore the relationship between chromosomal abnormalities and diseases in children by analyzing chromosome karyotypes. Methods The chromosome karyotype analysis of peripheral lymphocytes in 5 329 children was performed. Results In all, abnormal karyotype were found in 1 723 cases (32.33％) , in which the numerical chromosome abnormalities were detected in 1 539 (89.32％) , following by 125 cases of structural chromosome abnormalities (7.25％) , 53 cases of sex reverse syndrome (3.08％) , and 6 cases of true hermaphroditism (0.35％). The chromosome polymorphism were detected in 228 cases (4.28％). Conclusions The numerical chromosome abnormalities is most frequent chromosomal aberration and is one of the important causes that result in mental retardation, growth delay and disorders of sex development in children.