HOMOCYSTINURIA DUE TO DEFECT OF N(5,10)-METHYLENE THF DEFICIENCY (MTHFR)

Question 1

What is  HOMOCYSTINURIA DUE TO DEFECT OF N(5,10)-METHYLENE THF DEFICIENCY (MTHFR)?

Accepted Answer

rare (>170 cases)
autosomal recessive
mutation in the MTHFR gene
one turkish patient known to the authors (unpublished) with paraplegia, mental retardation and typical laboratory findings

Question 2

Gibt es eine deutsche Bezeichnung?

Accepted Answer

Hyperhomocysteinämie durch MTHFR [Methylen-Tetrahydrofolat-Reduktase]-Mangel

Question 3

What is the link to OMIM ?

Accepted Answer

OMIN 236250

Question 4

Which enzymes are involved?

Accepted Answer

N(5,10) methylenetetrahydrofolate reductase

Disease	HOMOCYSTINURIA DUE TO DEFECT OF N(5,10)-METHYLENE THF DEFICIENCY (MTHFR)
Synonym	MTHFR DEFICIENCY
OMIM	236250 OMIM = Online Mendelian Inheritance of Men
Orphanet	395
Protein (UniProt)	N(5,10) methylenetetrahydrofolate reductase
ExPASy	1.5.1.20
Gene locus	1p36.22
ICD	E72.1
Summary	rare (>170 cases) autosomal recessive mutation in the MTHFR gene one turkish patient known to the authors (unpublished) with paraplegia, mental retardation and typical laboratory findings
Laboratory findings	Betaine normal/inc (urine) Homocysteine inc (plasma) Methionine normal/dec (plasma) 5-Hydroxyindolacetic acid (5-HIAA) n/d (cerebrospinal fluid) 5-Methyltetrahydrofolate (5-MTHF) dec (cerebrospinal fluid) Homovanillic acid (HVA) n/d (cerebrospinal fluid) 5,10-Methylenetetrahydrofolate reductase dec (liver) 5,10-Methylenetetrahydrofolate reductase dec (fibroblasts) L-Homocystine inc (urine) L-Homocystine inc (plasma)
Symptoms	mental retardation ataxia behavior, abnormal or bizarre, confusion depression developmental regression encephalopathy gait disturbance hydrocephalus intellectual disability/intellectual developmental disorder microcephaly (<2 SD for age) MRI, brain, abnormalities [-] muscle weakness myopathy peripheral neuropathy psychosis seizures seizures, myoclonic thromboembolism dislocated lens (ectopia lentis) early death EEG abnormalities [-] feeding difficulties, poor feeding movement disorder, hyperkinetic MRI, brain, white matter abnormalities [-] onset, adolescent onset, adulthood onset, childhood onset, infancy onset, neonatal paraparesis/paraplegia paresis periventricular white matter changes tachypnea, hyperpnea, dyspnea, hyperventilation