Comparison of results of prenatal diagnosis by different techniques for fetuses with increased nuchal translucency / 中华医学遗传学杂志

OBJECTIVE@#To assess the value of chromosomal microarray analysis (CMA) and trio-whole exome sequencing (trio-WES) for fetuses with increased nuchal translucency (NT) thickness.@*METHODS@#Sixty two pregnant women who had visited Urumqi Maternal and Child Care Health Hospital between June 2018 and June 2020 for NT ≥ 3.0 mm at 11 ~ 13+6 gestational weeks were selected as study subjects. Relevant clinical data were collected. The patients were divided into 3.0 ~ ＜3.5 mm (n = 33) and ≥3.5 mm groups (n = 29). Chromosome karyotyping analysis and chromosomal microarray analysis were carried out. And trio-WES analysis was performed on 15 samples with NT thickening but negative CMA results. The distribution and incidence of chromosomal abnormalities in the two groups were compared by using chi-square test.@*RESULTS@#The median age of the pregnant women was 29 years old (22 ~ 41 years old), the median thickness of NT was 3.4 mm (3.0 ~ 9.1 mm), and the median gestational age at the detection was 13+4 weeks (11+5 ~ 13+6 weeks). Chromosome karyotyping analysis has detected 12 cases of aneuploidies and 1 case of derivative chromosome. The detection rate was 20.97% (13/62). CMA has detected 12 cases of aneuploidies, 1 case of pathogenic CNV and 5 cases of variant of uncertain significance (VUS), with a detection rate of 29.03% (18/62). The aneuploidy rate for the NT ≥ 3.5 mm group was higher than that for the 3.0 ≤ NT < 3.5 mm group [3.03% (1/33) vs. 41.38% (12/29), χ² = 13.698, P < 0.001]. There was no statistically significant difference between the two groups in the detection rate of fetal pathogenic CNV and VUS (χ² = 0.028, P > 0.05). Trio-WES analysis of 15 samples with negative CMA result and no structural abnormality has identified 6 heterozygous variants, including SOS1: c.3542C>T (p.A1181V) and c.3817C>G (p.L1273V), COL2A1: c.436C>T (p.P146S) and c.3700G>A (p.D1234N), LZTR1: c.1496T>C (p.V499A), and BRAF: c.64G>A (p.D22N), respectively. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), all of the variants were rated as VUS.@*CONCLUSION@#NT thickening can indicate chromosome abnormality, and CMA and trio-WES may be used for the prenatal diagnosis.

Application for prenatal diagnosis using both chromosomal karyotype analysis and BACs-on-Beads assay / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the application value in prenatal diagnosis using karyotype analysis combined with BACs-on-Beads (BoBs) assay.</p><p><b>METHODS</b>Nine hundred sixty five pregnant women were subjected to amniocentesis, chromosomal karyotype analysis and detection of BoBs were employed simultaneously for abnormal number of chromosomes and 9 chromosome microdeletion syndrome in prenatal diagnosis.</p><p><b>RESULTS</b>Fifty cases common chromosome aneupoidies were successfully detected by both karyotype analysis and BoBs which included 31 cases of trisomy 21,10 cases of trisomy 18 and 9 cases with sex chromosome abnormality. BoBs in addition detected 1 case of DiGeorge-1 microdeletion syndrome and 1 case of 7q11.23 microduplication syndrome. All 9 fetuses with chromosome abnormalities detected by karyotyping were missed by BoBs, including 2 cases of marker chromosomes,4 cases of chromosomal translocation,1 case of chromosomal inversion, 2 cases of Sex chromosome mosaicism; 2 cases of fetal inherited from the parents,7 cases for novel mutations.</p><p><b>CONCLUSION</b>Karyotype analysis combined with BoBs dedtection is a rapid, effective and highly accurate prenatal diagnosis model that may should be widely used in clinical diagnosis.</p>

Prenatal diagnosis of a rare case of 7q11.23 duplication syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the application of combined techniques for the prenatal diagnosis of a case with 7q11.23 duplication.</p><p><b>METHODS</b>Amniocentesis was performed in the second trimester for a mother with a high risk suggested by serological prenatal screening. G-banded chromosomal analysis was performed on cultured amniocytes and peripheral blood samples from both parents. DNA from amniotic fluid sample was isolated for a BACs-on-Beads (BoBs) assay. To define the range of duplication, copy number variation was determined with single nucleotide polymorphism array (SNP array, Affymetrix CytoScan 750K) and fluorescence in situ hybridization (FISH) analysis.</p><p><b>RESULTS</b>Chromosomal analysis suggested that the fetus and both parents all had a normal karyotype, while a duplication of 7q11.23 was detected by the BoBs assay. SNP array revealed a 1.5 Mb duplication in chromosome 7q11.23, which was confirmed by FISH.</p><p><b>CONCLUSION</b>Combined prenatal BoBs, SNP array and FISH has enabled effective diagnose of a case with 7q11.23 syndrome.</p>

The significance of lymph node dissection in the VI area of cN0 thyroid papillary carcinoma / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#The significance of lymph node dissection in the VI area of cN0 thyroid papillary carcinoma.@*METHOD@#Collect 150 cases of patients diagnosed with cNO thyroid papillary carcinoma and they were performed thyroid gland lobe and isthmic portion excision including lateral VI area lymph node cleaning. The specimens were pathologic examined to determinate the size, the position, invasion of thyroid papillary carcinoma,the number and metastasis of lymph node, etc.@*RESULT@#In the 150 patients performed the lymph node VI area groups cleaning, 93 cases had VI area of lymph node metastases, so the transfer rate was 62.0%. In the VI area, metastasis rate of tracheal side lymph nodes was 62.0% (93/150), lymph node before throat group was 4.67% (7/150), lymph node before trachea group was 3.33% (5/150), lymph nodes near the trachea laryngeal recurrent nerve ventral group was 52.0% (78/150), and next to the trachea laryngeal recurrent nerve dorsal lymph node group was 21.33% (32/ 150).@*CONCLUSION@#In CN0 thyroid papillary carcinoma, VI zone of lymph node metastasis rate is high, and region VI lymph node metastasis rate from high to low in order for: paratracheal lymph node, prelaryngeal lymph node, pretracheal lymph node. The metastasis rate of paratracheal throat back nerve ventral lymph node was the highest in central lymph node.