Defective GALM causes GALAC4

Stable Identifier
R-HSA-9931929
Type
Pathway
Species
Homo sapiens
ReviewStatus
5/5
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Defective GALM causes GALAC4
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GALM is a cytosolic enzyme that catalyzes the interconversion of beta-D-galactose to alpha-D-galactose. GALM conversion of b-GAL to a-GAL is required prior to a-GAL phosphorylation by galactokinase (GALK), the first committed step of galactose catabolism (Ai et al, 1995; Timson and Reese, 2003).
Mutations in GALM are associated with galactosemia type 4 (MIM 618881). Affected individuals generally present with mild symptoms which may include abnormal galactose levels, transient cholestasis and cataracts; more severe cases are associated with damage to kidney, liver and brain (Wada et al, 2019; Iwasawa et al, 2019; reviewed in Banford and Timson, 2021; Kikuchi et al, 2021).
Literature References
PubMed ID Title Journal Year
34842598 The Discovery of GALM Deficiency (Type IV Galactosemia) and Newborn Screening System for Galactosemia in Japan

Kikuchi, A, Wada, Y, Ohura, T, Kure, S

Int J Neonatal Screen 2021
12753898 Identification and characterisation of human aldose 1-epimerase

Timson, DJ, Reece, RJ

FEBS Lett. 2003
30910422 The prevalence of GALM mutations that cause galactosemia: A database of functionally evaluated variants

Iwasawa, S, Kikuchi, A, Wada, Y, Arai-Ichinoi, N, Sakamoto, O, Tamiya, G, Kure, S

Mol Genet Metab 2019
33181226 The structural and molecular biology of type IV galactosemia

Banford, S, Timson, DJ

Biochimie 2021
7542884 Comparison of the enzymatic activities of human galactokinase GALK1 and a related human galactokinase protein GK2

Ai, Y, Basu, M, Bergsma, DJ, Stambolian, D

Biochem Biophys Res Commun 1995
30451973 Biallelic GALM pathogenic variants cause a novel type of galactosemia

Wada, Y, Kikuchi, A, Arai-Ichinoi, N, Sakamoto, O, Takezawa, Y, Iwasawa, S, Niihori, T, Nyuzuki, H, Nakajima, Y, Ogawa, E, Ishige, M, Hirai, H, Sasai, H, Fujiki, R, Shirota, M, Funayama, R, Yamamoto, M, Ito, T, Ohara, O, Nakayama, K, Aoki, Y, Koshiba, S, Fukao, T, Kure, S

Genet Med 2019
Participants
Events
Participates
as an event of
Disease
Name Identifier Synonyms
galactosemia 4 DOID:0060969 GALM deficiency, Galactosemia type 4, Galactose mutarotase deficiency
Cross References
Mondo
Authored
Rothfels, K  (2024-12-13)
Reviewed
D'Eustachio, P  (2025-01-23)
Created
Rothfels, K  (2024-12-13)
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