染色体核型分析及array CGH在超声异常胎儿诊断中的应用

Application of chromosomal karyotyping analysis and array CGH for fetal abnormalities detected by ultrasonography

目的探讨染色体核型分析及微阵列芯片比较基因组杂交.（array-based comparativegenomic hybridization,array CGH）对于超声异常胎儿的产前诊断的价值。方法对1603份以胎儿超声标记异常为指征的孕妇的脐血样本进行染色体核型分析，对其中792例同时进行arrayCGH检测。结果在1603例胎儿的脐血样本中，共发现117例（7．30％）异常核型，其中染色体数目异常72例（4．49％），结构异常45例（2．81％）。非高龄组（〈35岁）与高龄组（≥35岁）孕妇胎儿异常核型的发生率的差异有统计学意义（χ2=30．687，P〈O．01）。不同超声异常项数目（单项、两项、合并多项）的孕妇的胎儿染色体异常检出率差异有统计学意义（χ2=85．507，P〈0．001）。在736例染色体核型为正常的样本中，arrayCGH共检出17例微缺失或微重复，检出率为2．31％。结论对于超声提示的胎儿异常，不论其为单项、两项、还是3项以上，均建议其采用染色体核型和arrayCGH分析进行产前诊断。

Objective To assess the value of chromosomal karyotyping and array-based comparative genomic hybridization for the diagnosis of fetus with abnormalities detected by ultrasonography. Methods Umbilical cord blood samples were derived from 1 603 pregnant women. The samples were cultured for routine G-banding karyotype analysis. Among these, 792 samples have further subjected to array CGH analysis. Results Among the 1 603 fetuses, 117 （7.30%） were found with chromosomal abnormalities. These included 72 numerical aberrations and 45 structural abnormalities, which respectively accounted for 4.49% and 2.81% of all cases. For those 〈35 years and ≥35 years, a significant difference has been found in terms of fetal chromosomal abnormalities （χ2 = 30. 687, P〈0. 01）. And there was also a significant difference between those with isolated, two or multiple ultrasonographic markers （χ2 = 85.50, P〈0.01）. Among 736 fetuses with a normal karyotype, array CGH has detected 17 （2.31%） with a microdeletion or microduplication. Conclusion Karyotype analysis and array CGH should be offered to all fetuses with ultrasonography detected anomalies regardless the number of markers.