MASA syndrome

MASA syndrome is a rare X-linked recessive neurological disorder on the L1 disorder spectrum. MASA syndrome is a rare X-linked recessive neurological disorder on the L1 disorder spectrum. The acronym 'MASA' stands for the four main signs and symptoms associated with the syndrome:(1) mental retardation (mild to moderate intellectual disability), (2) aphasia (delayed onset of speech), (3) shuffling gait, and (4) adducted thumbs. Affected males may also have a variable dilatation(widening) of the third heart ventricle. MASA syndrome has been associated with variants in the L1CAM gene. The symptoms are typically more intensive in males, due to the fact that males inherit only one X-chromosome. A diagnosis can be made when the clinical features have been identified, mainly the four common signs and symptoms. This can then be confirmed by single-gene sequencing, where the L1CAM gene is examined for any possible variations. A diagnostic test prior-to-birth is possible and very reliable when the mother is a carrier of the diseased allele. First, it's necessary to determine the fetus' sex and then study the X-chromosomes inherited from the mother. The probability of transferring the variant X-chromosome to the descendants is 50% regardless of the sex of the fetus (as illustrated by the figure). Male descendants who inherit the varied X-chromosome will express the symptoms of the syndrome, on the other hand females who inherit the varied X-chromosome will become carriers of the mutated gene and will not show any symptoms or clinical features of the syndrome.