ABSTRACT
Objective To investigate the distribution of abnormal karyotypes and their associations with clinical manifestations of the infertile patients in southern Sichuan Province.Methods A total of 4 157 infertile patients who attended the Reproductive Medicine Center of our hospital from July 2018 to June 2021 were included.The chromosome karyotype in peripheral blood was detected by G-banding,and their semen analysis results,uterine development and other clinical data were collected.Results Among the 4 157 patients,chromosomal polymorphisms were found in 239 cases(5.75％),and abnormal karyotypes wee found 137 cases(3.30％).The abnormal karyotypes included 57 cases(41.61％)of sex chromosome aneuploidy,6 cases(4.38％)of Robertsonian transloca-tions,32 cases(23.36％)of balanced translocations,21 cases(15.33％)of chromosomal inversions,9 cases(6.57％)of mosai-cism,8 cases(5.84％)of marker chromosomes,3 cases(2.19％)of sex reversal and 1 case(0.73％)of sex chromosome deletion.In male patients with abnormal karyotypes,91.58％showed abnormal semen parameters,while in those with polymorphic karyotypes,55％had abnormal semen parameters.The patients with Turner syndrome had significantly smaller uterine dimensions(longitudinal,transverse,and anteroposterior)compared to the normal control group(P＜0.01).Conclusion Chromosomal abnormalities should be the important cause of infertility.Conducting karyotype analysis combining with clinical manifestations is crucial examination for the di-agnosis and reproductive guidance of infertile patients.
ABSTRACT
OBJECTIVE@#To provide prenatal diagnosis, pedigree analysis and genetic counseling for a pregnant woman who had given birth to a child featuring global developmental delay.@*METHODS@#A pregnant woman who underwent prenatal diagnosis at the Affiliated Hospital of Southwest Medical University in August 2021 was selected as the study subject. Peripheral blood samples were collected from the woman, her husband and child, in addition with amniotic fluid sample during mid-pregnancy. Genetic variants were detected by G-banded karyotyping analysis and copy number variation sequencing (CNV-seq). Pathogenicity of the variant was predicted based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). Candidate variant was traced in the pedigree to assess the recurrence risk.@*RESULTS@#The karyotypes of the pregnant woman, her fetus, and affected child were 46,XX,ins(18)(p11.2q21q22), 46,X?,rec(18)dup(18)(q21q22)ins(18)(p11.2q21q22)mat and 46,XY,rec(18)del(18)(q21q22)ins(18)(p11.2q21q22)mat, respectively. Her husband was found to have a normal karyotype. CNV-seq has revealed a 19.73 Mb duplication at 18q21.2-q22.3 in the fetus and a 19.77 Mb deletion at 18q21.2-q22.3 in her child. The duplication and deletion fragments were identical to the insertional fragment in the pregnant woman. Based on the ACMG guidelines, the duplication and deletion fragments were both predicted to be pathogenic.@*CONCLUSION@#The intrachromosomal insertion of 18q21.2-q22.3 carried by the pregnant woman had probably given rise to the 18q21.2-q22.3 duplication and deletion in the two offspring. Above finding has provided a basis for genetic counseling for this pedigree.