Kondoh T, Tonoki H, Matsumoto T, Tsukahara M, Niikawa N
Department of Human Genetics, Nagasaki University School of Medicine, Japan.
Hum Genet. 1988 Aug;79(4):377-8. doi: 10.1007/BF00282181.
The parental origin of an extra chromosome in five patients with trisomy 18 was traced using a restriction fragment length polymorphism (RFLP) of the human prealbumin (PA) gene, localized to 18p11.1-q12.1, as a genetic marker. MspI digests of the genomic DNAs of the five patients, their parents and normal controls were hybridized with the PA-cDNA. Densitometric analysis on the gene dose of the polymorphic fragments of these patients revealed that three had originated from a maternal meiotic error. The other two patients were uninformative for the parental origin of trisomy 18. Our results indicate that nondisjunctional errors leading to trisomy 18 may occur predominantly at the maternal meiosis, consistent with the results of previous studies on the parental origin of trisomies 21 and 13.
利用定位于18p11.1-q12.1的人前白蛋白（PA）基因的限制性片段长度多态性（RFLP）作为遗传标记，追踪了5例18三体综合征患者额外染色体的亲本来源。对这5例患者及其父母和正常对照的基因组DNA进行MspI酶切，然后与PA-cDNA杂交。对这些患者多态性片段的基因剂量进行光密度分析，结果显示其中3例源于母本减数分裂错误。另外2例患者在18三体的亲本来源方面信息不明确。我们的结果表明，导致18三体的不分离错误可能主要发生在母本减数分裂过程中，这与先前关于21三体和13三体亲本来源的研究结果一致。
