Yntema et al. (1998) reported a large Dutch family in which 12 males in 3 generations were affected with nonspecific X-linked mental retardation. Of 9 examined patients, 6 showed moderate mental retardation, and 1 each showed mild, severe, ... Yntema et al. (1998) reported a large Dutch family in which 12 males in 3 generations were affected with nonspecific X-linked mental retardation. Of 9 examined patients, 6 showed moderate mental retardation, and 1 each showed mild, severe, and profound mental retardation. Obligate female carriers were all normal.
Among 119 unrelated male patients with nonspecific mental retardation, Kutsche et al. (2000) identified a mutation in the ARHGEF6 gene (300267.0001) in a patient from the large family with X-linked mental retardation described by Yntema et al. (1998). ... Among 119 unrelated male patients with nonspecific mental retardation, Kutsche et al. (2000) identified a mutation in the ARHGEF6 gene (300267.0001) in a patient from the large family with X-linked mental retardation described by Yntema et al. (1998). Further analysis showed that all affected members of the family had the mutation.