Hyperphosphatasia with mental retardation syndrome
Encyclopedia
Hyperphosphatasia with Mental retardation syndrome, HPMRS , also known as Mabry syndrome, has been described in patients recruited on four continents world-wide. Mabry syndrome was confirmed to represent an autosomal recessive syndrome characterized by severe mental retardation, considerably elevated serum levels of alkaline phosphatase
, hypoplastic terminal phalanges, and distinct facial features that include: hypertelorism, a broad nasal bridge and a rectangular face.
gene , there may be genetic heterogeniety in the spectrum of Mabry syndrome as a whole. PIGV is a member of the molecular pathway that synthesizes the Glycosylphosphatidylinositol anchor . The loss in PIGV activity results in a reduced anchoring of alkaline phosphatase to the surface membrane and an elevated alkaline phosphatase activity in the blood serum
.
Alkaline phosphatase
Alkaline phosphatase is a hydrolase enzyme responsible for removing phosphate groups from many types of molecules, including nucleotides, proteins, and alkaloids. The process of removing the phosphate group is called dephosphorylation...
, hypoplastic terminal phalanges, and distinct facial features that include: hypertelorism, a broad nasal bridge and a rectangular face.
Pathogenesis
While many cases of HPMRS are caused by mutations in the PIGVPIGV
GPI mannosyltransferase 2 is an enzyme that in humans is encoded by the PIGV gene.-Further reading:...
gene , there may be genetic heterogeniety in the spectrum of Mabry syndrome as a whole. PIGV is a member of the molecular pathway that synthesizes the Glycosylphosphatidylinositol anchor . The loss in PIGV activity results in a reduced anchoring of alkaline phosphatase to the surface membrane and an elevated alkaline phosphatase activity in the blood serum
Blood serum
In blood, the serum is the component that is neither a blood cell nor a clotting factor; it is the blood plasma with the fibrinogens removed...
.