Friedman J M
Department of Medical Genetics, University of British Columbia, and Medical Genetics Research Unit, Child and Family Research Institute, Children's and Women's Hospital, Vancouver, British Columbia, Canada.
Prenat Diagn. 2009 Jan;29(1):20-8. doi: 10.1002/pd.2129.
Array genomic hybridization (AGH) can detect chromosomal gains or losses that are 100 times smaller than those identifiable by conventional cytogenetic methods. Genome-wide AGH can identify genomic imbalance that causes birth defects and mental retardation at least twice as frequently as conventional cytogenetic analysis. Using AGH as a prenatal test for fetal genomic imbalance offers the promise of detecting pathogenic gain or loss of genomic material more quickly and much more frequently than current methods. However, the chance of finding a result of uncertain clinical significance is much greater than with conventional cytogenetic analysis, and the benefit-cost ratio of doing AGH in addition to conventional cytogenetic analysis in pregnancies at high risk for Down syndrome is likely to be poor. Very little is known about the natural history and range of clinical variability associated with most pathogenic submicroscopic copy number variants (CNVs). It seems doubtful that patients can be adequately counseled for prenatal AGH testing in most cases because the risks and benefits are unknown. At present, AGH should be offered for prenatal diagnosis only if the pregnancy is at especially high risk of having a pathogenic CNV or if AGH is being done as part of a clinical trial.
阵列基因组杂交（AGH）能够检测到比传统细胞遗传学方法可识别的染色体增减小100倍的情况。全基因组AGH能够识别导致出生缺陷和智力迟钝的基因组失衡，其频率至少是传统细胞遗传学分析的两倍。将AGH用作胎儿基因组失衡的产前检测方法，有望比现有方法更快且更频繁地检测到基因组物质的致病性增减。然而，发现临床意义不确定结果的可能性比传统细胞遗传学分析要大得多，并且在唐氏综合征高危妊娠中，除传统细胞遗传学分析外再进行AGH检测的效益成本比可能很低。对于大多数致病性亚微观拷贝数变异（CNV）相关的自然病史和临床变异性范围，人们了解甚少。在大多数情况下，患者能否得到关于产前AGH检测的充分咨询似乎存疑，因为风险和益处尚不明确。目前，仅当妊娠具有特别高的致病性CNV风险，或者AGH作为临床试验的一部分进行时，才应提供AGH用于产前诊断。
