{Reference Type}: Case Reports
{Title}: Prenatal diagnosis of recurrent mosaic ring chromosome 13 of maternal origin.
{Author}: Chen CP;Chen CY;Chern SR;Chen SW;Wu FT;Chen WL;Lee MS;Wang W;
{Journal}: Taiwan J Obstet Gynecol
{Volume}: 60
{Issue}: 4
{Year}: Jul 2021
{Factor}: 1.944
{DOI}: 10.1016/j.tjog.2021.05.033
{Abstract}: <B>OBJECTIVE: </B>We present prenatal diagnosis of recurrent mosaic ring chromosome 13 [r(13)] of maternal origin.<BR><B>METHODS: </B>A 27-year-old woman underwent amniocentesis at 17 weeks of gestation because of a past history of fetal abnormality caused by mosaic r(13) in the previous fetus associated with fetal intrauterine growth restriction (IUGR), a karyotype of 46,XY,r(13)[23]/45,XY,-13[10]/46,XY,idic r(13)[2] and a maternal origin of abnormal r(13). The parental karyotypes were normal. During this pregnancy, amniocentesis revealed a karyotype of 46,XX,r(13)[12]/45,XX,-13[8] and a 22.80-Mb deletion of chromosome 13q31.3-q34. The pregnancy was subsequently terminated, and a malformed fetus was delivered with craniofacial dysmorphism. Repeat amniocentesis revealed a karyotype of 46,XX,r(13)(p11.1q31)[18]/45,XX,-13[12]. The placenta had a karyotype of 46,XX,r(13)(p11.1q31)[27]/45,XY,-13[13]. Polymorphic DNA marker analysis using the DNA derived from the parental bloods and umbilical cord confirmed a maternal origin of the abnormal r(13).<BR><B>CONCLUSIONS: </B>Prenatal diagnosis of mosaic r(13) in consecutive pregnancies should raise a suspicion of parental gonadal mosaicism, and polymorphic DNA marker analysis is useful for determination of the parental origin of recurrent aneuploidy under such a circumstance.