Behavioral aspects of chromosomal variants

Abstract

Humans with chromosome aberrations often show, along with many other findings, behavioral abnormalities, which may be mild or severe and may either affect all carriers of an aberration or only some of them. Although chromosome aberrations influence embryonic development in multiple and ill-defined ways, certain genetic syndromes do result in relatively specific patterns of behavior and related attributes. Although sophisticated approaches to examine such behavioral phenotypes have been developed, the description and characterization of behavioral aspects is also frequently accompanied by claims and counterclaims which often complicate the subject. Relative to the general population, individuals with intellectual disabilities are at much higher risk of experiencing behavioral, emotional, and psychiatric problems. However, many mental health professionals do not appreciate the co-occurrence of psychiatric problems and intellectual disabilities. Therefore, there are several gaps in the research and treatment of mental health concerns in people with autosomal chromosomal aberrations. Nevertheless, chromosomal aberrations offer the unique opportunity to relate behavioral phenomena to independently ascertained and relatively well-defined genetic causes. In this chapter the impact of various chromosomal rearrangements, ranging from whole-chromosome copy number changes to small deletions or duplications, on behavior is described and discussed.