disease has basis in dysfunction of MTR methylcobalamin deficiency type cblG DOID:0050733 EFO:0005597 GARD:0002733 GARD:0003577 HMAG ICD10:E72.1 MONDO:0009609 Methylcobalamin deficiency cbl G type is a rare condition that occurs when the body is unable to process certain amino acids (building blocks of protein) properly. In most cases, signs and symptoms develop during the first year of life; however, the age of onset can range from infancy to adulthood. Common features of the condition include feeding difficulties, lethargy, seizures, poor muscle tone (hypotonia), developmental delay, microcephaly (unusually small head size), and megaloblastic anemia. Methylcobalamin deficiency cbl G type is caused by changes (mutations) in the MTR gene and is inherited in an autosomal recessive manner. Treatment generally includes regular doses of hydroxycobalamin (vitamin B12). Some affected people may also require supplementation with folates and betaine. OMIM:250940 Orphanet:2170 SCTID:721187005 cblG functional methionine synthase deficiency type cblG homocystinuria due to defect in methylation Cbl g homocystinuria-megaloblastic Anemia due to defect in cobalamin metabolism, cblG complementation type homocystinuria-megaloblastic anemia, cblG complementation type https://rarediseases.info.nih.gov/diseases/3577/methylcobalamin-deficiency-cbl-g-type methionine synthase deficiency methylcobalamin deficiency Cbl G type methylcobalamin deficiency, cblG type methylmalonic aciduria and homocystinuria type cblG homocystinuria without methylmalonic aciduria thrombotic microangiopathy inherited blood coagulation disorder