Denomme Gregory A, Fernandes Bernard J
Research and Development, Canadian Blood Services, Toronto, Canada.
Transfusion. 2007 Jul;47(1 Suppl):64S-8S. doi: 10.1111/j.1537-2995.2007.01313.x.
Blood group genotyping using DNA extracted from fetal tissue is useful to identify fetuses at risk for hemolytic disease of the fetus and newborn (HDFN) due to maternal red cell alloantibodies. Four considerations are important for fetal blood group genotyping. First, paternal heterozygosity must be established, including tests that evaluate RHD hemizygosity. Second, the source of fetal tissue for DNA extraction requires certain considerations. Third, because the fetal genotype is used to predict the expressed phenotype, a thorough knowledge of blood group genetics is required. Moreover, the test algorithm should include the evaluation of the parental phenotypes and genotypes to help identify variant alleles. Fourth, the blood group antigen expression at birth should be evaluated to confirm the inheritance. The identification of an antigen-negative fetus on the basis of the blood group genotype provides significant advantages in managing the pregnancy at risk for HDFN. In the near future, fetal DNA in maternal plasma will likely replace fetal blood group genotyping for RHD. Significant challenges remain to detect other clinically significant blood group antigens using maternal plasma DNA.
使用从胎儿组织中提取的DNA进行血型基因分型，有助于识别因母体红细胞同种抗体而有患胎儿和新生儿溶血病（HDFN）风险的胎儿。胎儿血型基因分型有四个重要的考虑因素。首先，必须确定父亲的杂合性，包括评估RHD半合子性的检测。其次，用于DNA提取的胎儿组织来源需要一定的考虑。第三，由于胎儿基因型用于预测表达的表型，因此需要全面了解血型遗传学。此外，检测算法应包括对父母表型和基因型的评估，以帮助识别变异等位基因。第四，应评估出生时的血型抗原表达以确认遗传情况。基于血型基因型鉴定出抗原阴性胎儿，在管理有HDFN风险的妊娠方面具有显著优势。在不久的将来，母血血浆中的胎儿DNA可能会取代用于RHD的胎儿血型基因分型。使用母血血浆DNA检测其他临床上重要的血型抗原仍存在重大挑战。
