X-linked mental retardation refers to medical disorders associated with X-linked recessive inheritance that result in intellectual<unk> . As with most X-linked disorders, males are more heavily affected than females. Females with one affected X chromosome and one normal X chromosome tend to have milder symptoms. Unlike many other types of intellectual<unk> , the genetics of these conditions are relatively well understood. It has been estimated there are ~200 genes involved in this syndrome; of these ~100 have been identified. Many of these genes are found on the short 'p' arm of the chromosome, and duplications at Xp11.2 are associated with the syndromic form of the condition. X-linked mental retardation accounts for ~16% of all cases of intellectual<unk>  in males.
X-linked intellectual disability
SYNGAP1-related intellectual disability
SYT1-associated neurodevelopmental disorder
Multiple complex developmental disorder
Trichothiodystrophy
MECP2 duplication syndrome
Zellweger spectrum disorders
Fragile X syndrome