Pseudoisodicentric bisatellited extra marker chromosome (tetrasomy 22pter----q11, trisomy Yqh), derived from a maternal Y/22 translocation. Association between this tetrasomy and "cat eye" phenotypical features.

A patient with multiple congenital anomalies suggestive of the "Cat eye" syndrome was found to have an extra marker bisatellited chromosome 22 derived from a maternal Y/22 translocation, identified by multiple banding patterns in cultures treated with DA. The proband's karyotype is 47,XX, + psu idic(22)(Yqter----Yq12::22p13----22q11::++ +22q11----22p13::Yq12----Yqter), t(22;Y)(p13;q12)mat., being tetrasomic for 22pter----q11, and trisomic for Yqh. Similarity between his clinical features and reported "Cat eye" cases, confirms that this region is responsible for the phenotypical expression of the syndrome.