Piebaldism is a rare, autosomal dominant disorder characterized
by the congenital absence of melanocytes in affected areas of
the skin and hair. We report on a familial 4q12 deletion that involves
the KIT gene and causes piebaldism in affected individuals. Wholegenome
genotyping analysis of the proband using HumanCytoSNP-
12v2.1 BeadChips (Illumina Inc., San Diego, CA, USA, revealed a 1.34-Mb
microduplication of 1q21.1q21.2 and a 2.7-Mb microdeletion of 4q12.
The analysis of the parents confirmed the paternal origin of the 4q12
microdeletion. The clinical and molecular findings in the proband and
his affected relatives showed that the 2.7-Mb 4q12 microdeletion, the
smallest microdeletion reported to date, causes isolated piebaldism
due to the loss of the KIT gen
