hyperlysinemia

A metabolic disorder characterized by mental retardation, convulsions, anemia, and asthenia; associated with an abnormal increase of the amino acid lysine in the circulating blood due to a deficiency of lysine-ketoglutarate reductase. One variant [MIM*268700] is associated with a deficiency of α-aminoadipic semialdehyde synthase, resulting in h. and saccharopinemia.

* * *

hy·per·ly·sin·emia (hi″pər-li″se-neґme-ə) 1. excess of lysine in the blood. 2. an autosomal recessive aminoacidopathy due to mutation in the AASS gene (locus: 7q31.3), which encodes α-aminoadipic semialdehyde synthase, causing deficiency of both of its enzyme activities (lysine-ketoglutarate dehydrogenase and saccharopine dehydrogenase); it is characterized by excess of lysine and, to a lesser degree, saccharopine, in the blood and urine. Cf. saccharopinuria.