Application of flat-sided culture tubes during prenatal diagnosis / 中华医学遗传学杂志

OBJECTIVE@#To assess the value of using flat-sided culture tubes for preparing chromosomes through chorionic villi (CV) and amniotic fluid (AF) cell cultures during prenatal diagnosis.@*METHODS@#From February to March 2020, 157 CV samples and 147 AF samples subjected to prenatal diagnosis at the Maternal and Child Health Care Hospital of Guangxi Zhuang Autonomous Region were selected as the study subjects. For each sample, one flat-sided tube and one flask culture were set up by following the standard protocols. The methods were evaluated by comparing the cell growth, experimental process, quality of chromosome preparation and costs.@*RESULTS@#The success rates for the culturing of CV and AF samples by the flat-sided culture tube method were 97.45% (153/157) and 97.96% (144/147), respectively. By contrast, the success rates for the conventional flask method were 98.72% (155/157) for CV and 98.64% (145/147) for AF samples. No significant difference was found between the two methods (P > 0.05). The average harvest time required by the flat-sided culture tube method was 8.45 days for CV and 9.43 days for AF cultures, whilst the average harvest time for conventional flask method was 9.05 days and 9.54 days, respectively. The flat-sided culture tube method for CV had required significantly shorter average harvest time than the conventional method (P < 0.001). No statistical significant difference was found in the average harvest time for AF by the two methods (P > 0.05). The conventional culturing method had required three containers with two sample transfers. By contrast, the flat-sided culture tube method was carried out in one tube without any sample transfer. The average total amount of medium used was 3.91 mL for each flat-sided culture tube and 6.26 mL for each conventional flask.@*CONCLUSION@#The flat-sided culture tube method can provide a simple, cost-effective and error-reducing procedure for the CV and AF samples culture during prenatal diagnosis.

Genetic analysis of homologous Robertsonian translocation trisomy 21 in 12 pedigrees / 中华围产医学杂志

Objective:To analyze the genetic features of homologous Robertsonian translocation trisomy 21.Methods:This retrospective analysis involved 12 pedigrees in which singleton fetuses were prenatally diagnosed with homologous Robertsonian translocation trisomy 21 [46,XX/XY,+21,der(21;21)(q10;q10)] at the Maternal and Child Health Hospital of Guangxi Zhuang Autonomous Region from January 2012 to January 2023. Moreover, karyotype analysis results of the parental peripheral blood were obtained. The prenatal diagnosis results and genetic features in the 12 pedigrees were summarized using descriptive statistical analysis.Results:Among the 12 pedigrees, eight cases were de novo and the other four were maternally inherited. Three mothers in the four inherited cases had homologous Robertsonian translocation trisomy 21 and the other one was a homologous Robertsonian translocation carrier. The karyotypes of the four fathers were all normal. There were three families with multiple children, two of the couples with normal karyotypes had normal children, and the other couple had a child with homologous Robertsonian translocation trisomy 21 that was inherited from the mother with the same type of trisomy 21. Non-invasive prenatal testing was performed in two pedigrees during this pregnancy and the results showed that one case was at low risk and one was at high risk of trisomy 21. Further testing of the placenta after labor induction confirmed the low-risk case with low proportion of mosaic trisomy 21 (the proportion was 21% on the maternal side of the placenta and 9% on the fetal side). Conclusions:Most cases of homologous Robertsonian translocation trisomy 21 are de nove and few are inherited. Parents of probands with homologous Robertsonian translocation trisomy 21 should be routinely advised to undergo peripheral blood chromosome examination to find out whether they are carriers of homologous Robertsonian translocation.

Analysis of fetal chromosomal karyotypes in 1 160 pregnant women during the first trimester of gestation / 重庆医学

Objective To evaluate the value of chorionic villus cells karyotype analysis in prenatal diagnosis during the first tri-mester of pregnancy.Methods Pregnant women with prenatal diagnosis indications were punctured by guiding abdominal B-mode ultrasound to get villi tissue which was then to develop cell culture,chromosome preparation and karyotype analysis.Results A to-tal of 1 140 cases were successfully cultured,and the successful cultivating rate was 98.2% (1 140/1 160).Among them,chromo-somes of 62 cases were detected to be non-polymorphic structural abnormalities,including 32 abnormal chromosome number,5 chro-mosome balanced translocation,3 chromosome deletion,and 22 chimeras.What′s more,20 cases were detected to be chromosomal inversion,19 cases of chromosome 9 were inversion,and one with chromosome Y was inversion.Conclusion Karyotype analysis of villus cell could help to detect fetal chromosomal abnormalities during early pregnancy and get early intervention.It was significant to reduce the child′s birth with chromosome abnormalities.