Phenotypic Variability in Obsessive-Compulsive Disorder and Its Relationship to Familial Risk
ABSTRACTTwin and family studies of obsessive-compulsive disorder (OCD) have gleaned important data regarding the influence of genetic factors in the development of this disorder. These studies have shown that understanding the importance of genetic factors in OCD is largely dependent upon how the phenotype is classified. The last decade of research has found that substantial variability of symptomatology exists across individuals diagnosed with OCD. Considering this, a number of analyses have been conducted to determine if possible subtypes of OCD exist, including analysis of age of onset, cluster analysis, factor analysis, and segregation analysis. These methodologies, and possibly others, could aid in identifying the genes involved in the development of OCD.