背景:目前可以通过非侵入性初步筛查(NIPS)检测到亚染色体缺失和重复。然而,NIPS是一种需要进一步诊断的筛查试验。在这里,我们报告了NIPS和常规核型结合拷贝数变异测序(CNV-seq)揭示的常染色体异常的胎儿,证实了胎儿的不平衡易位。
方法:这是一名30岁女性的第4次妊娠,该女性经历了2次自然流产并生下了一个表型正常的孩子。该妇女和她的丈夫健康且没有血缘关系。NIPS在妊娠17周时在16q22.1-q22.4区域显示约19-Mb片段的重复。
方法:传统核型与CNV-seq相结合,可以更好地定位异常染色体区域,进一步确定胎儿染色体异常的来源。同时,我们通过超声检查评估胎儿形态。胎儿核型为46,XX,der(7)t(7;16)(p22;q23)和CNV-seq结果显示在16q22.1-q24.3(69200001-90160000)中大约有20.96-Mb重复,在7p22.3-p22.2(40001-3900000)中大约有3.86-Mb缺失。产前超声显示胎儿微颌骨畸形。父系核型为46,XY,t(7;16)(p22;q23),而产妇是正常的。胎儿从其父亲那里继承了异常的7号染色体。
方法:不对胎儿进行治疗。
结果:终止妊娠。
结论:据我们所知,从头部分三体性16q(16q22.1-qter)和部分单体性7p(7p22.2-pter)的发生到目前为止尚未报道。这里,我们介绍了此类病例的围产期发现和文献综述。CNV-seq与核型结合是NIPS指示的染色体异常的有用工具。
BACKGROUND: Subchromosomal deletions and duplications could currently be detected by noninvasive preliminary screening (NIPS). However, NIPS is a screening test that requires further diagnosis. Here we report a fetus with an autosomal abnormality revealed by NIPS and conventional karyotype combined with copy number variations sequencing (CNV-seq) confirmed the fetus with an unbalanced translocation.
METHODS: This was the fourth pregnancy of a 30-year-old woman who underwent 2 spontaneous abortions and gave birth to a child with a normal phenotype. The woman and her husband were healthy and nonconsanguineous. NIPS indicated a repeat of about 19-Mb fragment at the region of 16q22.1-q22.4 at 17-week gestation.
METHODS: The combination of traditional karyotype and CNV-seq could better locate the abnormal chromosomal region and further identify the source of fetal chromosomal abnormalities. Simultaneously, we evaluated the fetal morphology by ultrasound examination. The karyotype of the fetus was 46,XX,der(7)t(7;16)(p22;q23) and CNV-seq results showed an approximately 20.96-Mb duplication in 16q22.1-q24.3 (69200001-90160000) and an approximately 3.86-Mb deletion in 7p22.3-p22.2 (40001-3900000). Prenatal ultrasound revealed the fetal micrognathia. The paternal karyotype was 46,XY, t (7;16) (p22;q23), while the maternal was normal. The fetus inherited an abnormal chromosome 7 from its father.
METHODS: No treatment for the fetus.
RESULTS: Pregnancy was terminated.
CONCLUSIONS: To our knowledge, the occurrence of de novo partial trisomy 16q (16q22.1-qter) and partial monosomy 7p (7p22.2-pter) has not previously been reported up to now. Here, we present the perinatal findings of such a case and a review of the literatures. CNV-seq combined with karyotype is a useful tool for chromosomal abnormalities indicated by NIPS.