ABSTRACT
Methods:A total of 1 152 amniotic fluid samples were collected from pregnant women who underwent prenatal diagnosis in the Nanjing Maternity and Child Health Care Hospital, Women′s Hospital School of Medicine Zhejiang University, West China Second University Hospital, Sichuan University/West China Women′s and Children′s Hospital, and Xiamen Maternal and Child Health Hospital from September 2014 to August 2016. These samples were examined with SD-HRM and karyotyping simultaneously. Clinical sensitivity and specificity of SD-HRM were calculated, and Kappa values were measured to evaluate the consistency of detection results of the two methods.Results:A total of 161 cases of trisomy 21, 60 cases of trisomy 18, and 5 cases of trisomy 13 were detected by SD-HRM in 1 152 prenatal samples, sensitivity and specificity were both up to 100%, and Kappa values is equal to 1 which were consistent with the results of karyotype analysis.Conclusion:SD-HRM is validated to be highly accurate for the prenatal diagnosis of common trisomies, which is promising in the clinical practice.
ABSTRACT
Chromosomal microdeletion and microduplication syndromes are common genetic diseases.Technologies including fluorescence in situ hybridization , chromosomal microarray , real-time PCR, multiplex ligation-dependent probe amplification and high-throughput sequencing have been used to detect these diseases . The advantages and limitations of these technologies as well as their clinical applications in the detection of chromosomal microdeletion and microduplication syndromes are analyzed . (Chin J Lab Med, 2016, 39:407-409 )
ABSTRACT
Objective To evaluate application feasibility of Array CGH in genetic diagnosis of clinical complex chromosomal abnormalities.Methods Two patients of genetic counseling and two patients of prenatal diagnosis were selected from Xiamen Maternity & Child Health Care Hospital during the period of December 2010 to December 2011.Under aseptic conditions 2-4 ml peripheral blood was collected in EDTA and 2-3 ml Cord Blood was collected through cordocentesis after genetic counseling and preoperative examination.G-banded chromosome analysis and genome DNA extraction were carried out on the four cases.The whole genome of four cases were scanned and analyzed by Array CGH.The results of Array CGH were confirmed by FISH.Results Array CGH detected different kinds of duplications and deletions in several chromosomes.Most of these duplications and deletions were not detected by karyotype analysis.The results of Array CGH showed duplication of 4p16.3-4p15.31,deletion of 4p16.3 in the first case,duplication of Xp11.22-Xq11.1 in the second case,duplication of 4p16.3-4p15.32,deletion of 2q37.3 in the third case and duplication of 2q21.2-2q32.1,deletion of 2q14.3-2q21.1 in the fourth case.These duplications and deletions were confirmed by FISH.Conclusions Compared with conventional cytogenetic analysis,Array CGH can not only accurately detect micro deletion and micro duplication with high resolution and sensitivity but also identify breakpoints precisely.Array CGH can provide the basis for clinical genetic diagnosis.