Mild phenotype in a patient with mosaic del(8p)/inv dup del(8p)

Abstract We report on a female with a mild phenotype who is mosaic for two cell lines with different structural abnormalities of 8p, both resulting in large genomic imbalances. Molecular cytogenetic and G‐banded chromosome analyses demonstrated that one cell line has a large terminal 8p deletion, with a breakpoint in 8p21.2. The other cell line contains a derivative chromosome 8, known as an inv dup del(8p) in the literature. This female has developmental delay, but lacks congenital anomalies that are associated with either 8p abnormality in non‐mosaic form. The attenuated phenotype in this individual may be due to compensation of one cell line for imbalances in the other cell line. © 2010 Wiley‐Liss, Inc.