Papoulidis I, Kontodiou M, Tzimina M, Saitis I, Hamid A B, Klein E, Kosyakova N, Kordass U, Kunz J, Siomou E, Nicolaides P, Orru S, Thomaidis L, Liehr T, Petersen M B, Manolakos E
Eurogenetica S.A., Thessaloniki and Athens, Greece.
Cytogenet Genome Res. 2012;136(4):237-41. doi: 10.1159/000337520. Epub 2012 Apr 5.
Tetrasomy 9p is a rare chromosomal syndrome and about 30% of known cases exhibit mosaicism. Approximately 50 of the reported cases with tetrasomy 9p mosaicism show a characteristic facial appearance, growth failure, and developmental delay. However, 3 patients with mosaicism for isochromosome 9p and a normal phenotype have also been reported. We report 2 additional cases of clinically normal young females with tetrasomy 9p mosaicism, one of whom also exhibited X chromosome aneuploidy mosaicism leading to an overall of 6 different cell lines. STR analysis performed on this complex mosaic case indicated that the extra isochromosome was of maternal origin while the X chromosome aneuploidy was of paternal origin, indicating a postzygotic event.
9号染色体短臂四体综合征是一种罕见的染色体综合征，约30%的已知病例表现为嵌合体。报道的约50例9号染色体短臂四体嵌合体病例呈现出特征性面容、生长发育迟缓。然而，也有3例9号等臂染色体嵌合体且表型正常的患者被报道。我们报告另外2例临床正常的9号染色体短臂四体嵌合体年轻女性病例，其中1例还表现出X染色体非整倍体嵌合体，导致共有6种不同的细胞系。对这一复杂嵌合体病例进行的STR分析表明，额外的等臂染色体来自母亲，而X染色体非整倍体来自父亲，提示这是一个合子后事件。
