A case of prenatally diagnosed Non-15, Non-22 marker chromosome / 대한산부인과학회지

ABSTRACT

Midtrimester genetic amniocentesis is an important diagnostic tool in prenatal genetic diagnosis and counseling. We can identify karyotypes with metaphase chromosome analysis of cultured amniocytes. Marker chromosomes are defined as unidentified structurally abnormal chromosomes. Incidence of marker chromosomes in the previous reported studies was 0.6-1.5/1,000. They occurred more frequently with advanced maternal age. Ascertainment of chromosomal origin is important because it may be associated with malformation and developmental abnormalities. Recently, identification of the origin and composition of marker chromosomes has been made possible by the use of fluorescent in situ hybridization (FISH). Most marker chromosomes are known to be originated from chromosome 15 or 22, X, Y. We have experienced a case of non-15, non-22 marker chromosome prenatally detected in amniocentesis and FISH, so we reported it with a brief review of literature.