Intellectual Disability: When the Hypertrichosis Is a Clue

The HHID syndrome of hypertrichosis, hyperkeratosis, abnormal corpus callosum, intellectual disability, and minor anomalies is caused by mutations in ARID1B

1 Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland 2Mehiläinen Clinic, Vantaa, Finland 3Department of Clinical Genetics, Helsinki University Central Hospital and Department of Medical Genetics, University of Helsinki, Helsinki, Finland 4National Institute for Health and Welfare, Helsinki, Finland 5Radiz–Rare Disease Initiative Zurich, Clinical Research Priority...

Congenital generalized hypertrichosis: the skin as a clue to complex malformation syndromes

Hypertrichosis is defined as an excessive growth in body hair beyond the normal variation compared with individuals of the same age, race and sex and affecting areas not predominantly androgen-dependent. The term hirsutism is usually referred to patients, mainly women, who show excessive hair growth with male pattern distribution.Hypertrichosis is classified according to age of onset (congenita...

Intellectual disability (mental retardation).

Aneuploidy and Intellectual Disability

Aneuploidy is the presence of an abnormal number of chromosomes in cells. The gain or loss of a chromosome in germ cells is the most common cause of chromosomal aneuploidy. Trisomy 21, trisomy 18, and trisomy 13 are characterized by congenital anomalies with intellectual disability (ID) or short lives. Recently, mosaic variegated aneuploidy (the presence of a different number of chromosomes in ...

Chapter 5: Intellectual disability

Pragmatic language skills are often impacted in individuals with intellectual disability, a developmental condition defined by deficits in intellectual and adaptive skills. In this chapter, we review the literature on pragmatic language in three genetically-based causes of intellectual disability – Down syndrome, fragile X syndrome, and Williams syndrome. We focus on groupcomparison studies of ...