A novel duplication of Xp is described. A 20-year-old man had minor anomalies ichthyosis, congenital heart defect, varicose veins, and hypogonadotropic hypogonadism. He had an interstitial duplication of approximately 2.8 Mb from chromosome region Xp22.31p22.2. His similarly affected brother and asymptomatic mother were shown to carry the same duplication. Knowledge about this duplication and its resultant phenotype will add to our understanding of the role of X chromosome duplications. © 2012 Wiley Periodicals, Inc.