Autosomal recessive disease characterized by sarcosine dehydrogenase deficiency. Controversies about clinical repercussion exist.
SAR Syndrome; Hypersarcosinemia Syndrome; Complex Deficiency of Sarcosine Dehydrogenase; SARD Deficiency; SARDH Deficiency.
1:14,900 to 1:350,000 live births (screening programs).
Caused by mutations in the SARDH gene located on 9q33-q34. Mutation causes deficient activity of sarcosine dehydrogenase and then accumulation of sarcosine, which could explain clinical manifestations.
Increased concentration of sarcosine in plasma and urine as a result of sarcosine dehydrogenase deficiency. Sarcosine is a key intermediate in 1-carbon metabolism and under normal circumstances is converted to glycine by the enzyme sarcosine dehydrogenase.
Usually a benign metabolic state that produces no clinical disease. Multiple symptoms have been reported in sarcosinemia such as mental retardation, growth failure, hepatomegaly, craniostenosis, syndactyly, and cardiomyopathy. There is large number of patients with a high level of sarcosine in plasma who do not present any symptoms. Reported association with clinical symptoms could be as a result of an ascertainment bias.
Precautions before anesthesia
Evaluate cardiac function (clinical, ECG, echocardiography).
Prophylactic antibiotics should be considered in case of cardiopathy.
There are no known specific implications with this condition.
et al: Mutations in the sarcosine dehydrogenase gene in patients with sarcosinemia. Hum Genet
et al: The mouse mutation sarcosinemia (SAR) maps to chromosome 2 in a region homologous to human 9q33-q34. Genomics
MS: Cloning and mapping of the cDNA for human sarcosine dehydrogenase, a flavoenzyme defective in patients with sarcosinemia. Genomics
HA: Hypersarcosinemia: An inborn error of metabolism. N Engl J Med