X-linked intellectual disability is a genetically heterogeneous condition, due to mutations in at least 50 genes located on the X chromosome, involved in functioning of the central nervous system. It is estimated to affect approximately 1 in 600 males. There are two categories of hereditary ID; isolated ID with no other consistent defining features, known as nonspecific or non-syndromic ID and syndromic ID, which presents with variable penetrance and expressivity. Although numerous genes responsible for syndromic intellectual disability have been identified, the study of non-syndromic intellectual disability faces challenges from intrinsic issues of genetic heterogeneity (Zemni et al., 2000).
Genetic landscape of XLID
In the past, it was estimated that a proportion of 20-25% of intellectual disability could be accredited to X-linked intellectual disability, but in the more recent years these numbers have changed pointing towards a 10-15%. However, the overall contribution of XLID will be truly determined when the causative mutations of a considerable amount of intellectual disability cases will be identified. The genetic landscape of XLID shows a vast number of rare, as well as unique single nucleotide mutations, which is also supported by the numbers of families having mutations in non-syndromic XLID genes. …show more content…
Structural abnormalities, such as facial clefting, cardiac and genitourinary malformations as well as hydrocephalus are the most common abnormalities that will probably require surgical intervention. Malformations of the central nervous system are another category of the XLID
Genetic landscape of XLID
In the past, it was estimated that a proportion of 20-25% of intellectual disability could be accredited to X-linked intellectual disability, but in the more recent years these numbers have changed pointing towards a 10-15%. However, the overall contribution of XLID will be truly determined when the causative mutations of a considerable amount of intellectual disability cases will be identified. The genetic landscape of XLID shows a vast number of rare, as well as unique single nucleotide mutations, which is also supported by the numbers of families having mutations in non-syndromic XLID genes. …show more content…
Structural abnormalities, such as facial clefting, cardiac and genitourinary malformations as well as hydrocephalus are the most common abnormalities that will probably require surgical intervention. Malformations of the central nervous system are another category of the XLID