No sexual predilection is observed because the deficiency of glycogen synthetase activity is inherited as an autosomal recessive trait.

The major morbidity is a risk of fasting hypoglycemia, which can vary in severity and frequency. Major long-term concerns include growth delay, osteopenia, and neurologic damage resulting in developmental delay, intellectual deficits, and personality changes.

A 2011 review of 176 cases found that diagnoses made early in life (within a few days of birth) were associated with more severe disease and a mortality of 33%. Children diagnosed later, and who had milder symptoms, showed a lower mortality rate of ~3%.

A 2001 study followed up on 50 patients. Of these 38% died in childhood while the rest suffered from problems with morbidity.

Canine phosphofructokinase deficiency is found mostly in English Springer Spaniels and American Cocker Spaniels, but has also been reported in Whippets and Wachtelhunds. Mixed-breed dogs descended from any of these breeds are also at risk to inherit PFK deficiency.

Enolase Deficiency is a rare genetic disorder of glucose metabolism. Partial deficiencies have been observed in several caucasian families. The deficiency is transmitted through an autosomal dominant inheritance pattern. The gene for Enolase 1 has been localized to Chromosome 1 in humans. Enolase deficiency, like other glycolytic enzyme deficiences, usually manifests in red blood cells as they rely entirely on anaerobic glycolysis. Enolase deficiency is associated with a spherocytic phenotype and can result in hemolytic anemia, which is responsible for the clinical signs of Enolase deficiency.

Less than 20 patients with MGA type I have been reported in the literature (Mol Genet Metab. 2011 Nov;104(3):410-3. Epub 2011 Jul 26.)

In order to get Tarui’s disease, both parents must be carriers of the genetic defect so that the child is born with the full form of the recessive trait. The best indicator of risk is a family member with PFK deficiency.

Management for mitochondrial trifunctional protein deficiency entails the following:

- Avoiding factors that might precipitate condition

- Glucose

- Low fat/high carbohydrate nutrition

This condition is sometimes mistaken for Reye syndrome, a severe disorder that develops in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections.

Symptoms can be reduced through avoidance of leucine, an amino acid. Leucine is a component of most protein-rich foods; therefore, a low-protein diet is recommended. Some isolated cases of this disorder have responded to supplemental biotin; this is not altogether surprising, consider that other biotin-related genetic disorders (such as biotinidase deficiency and holocarboxylase synthetase deficiency) can be treated solely with biotin. Individuals with these multiple carboxylase disorders have the same problem with leucine catabolism as those with 3-methylcrotonyl-CoA carboxylase deficiency.

The term fatty acid oxidation disorder (FAOD) is sometimes used, especially when there is an emphasis on the oxidation of the fatty acid.

In addition to the fetal complications, they can also cause complications for the mother during pregnancy.

Examples include:

- trifunctional protein deficiency

- MCADD, LCHADD, and VLCADD

It is one of the 29 conditions currently recommended for newborn screening by the American College of Medical Genetics.

Transaldolase deficiency is recognized as a rare inherited pleiotropic metabolic disorder first recognized and described in 2001 that is autosomal recessive. There have been only a few cases that have been noted, as of 2012 there have been 9 patients recognized with this disease and one fetus.

The presentation of mitochondrial trifunctional protein deficiency may begin during infancy, features that occur are: low blood sugar, weak muscle tone, and liver problems. Infants with this disorder are at risk for heart problems, breathing difficulties, and pigmentary retinopathy. Signs and symptoms of mitochondrial trifunctional protein deficiency that may begin "after" infancy include hypotonia, muscle pain, a breakdown of muscle tissue, and a loss of sensation in the extremities called peripheral neuropathy. Some who have MTP deficiency show a progressive course associated with myopathy, and recurrent rhabdomyolysis.

Mutations in the "HADHA" gene lead to inadequate levels of an enzyme called long-chain 3-hydroxyacyl-coenzyme A (CoA) dehydrogenase, which is part of a protein complex known as mitochondrial trifunctional protein. Long-chain fatty acids from food and body fat cannot be metabolized and processed without sufficient levels of this enzyme. As a result, these fatty acids are not converted to energy, which can lead to characteristic features of this disorder, such as lethargy and hypoglycemia. Long-chain fatty acids or partially metabolized fatty acids may build up in tissues and damage the liver, heart, retina, and muscles, causing more serious complications.

Mutations in the "HADH" gene lead to inadequate levels of an enzyme called 3-hydroxyacyl-coenzyme A dehydrogenase. Medium-chain and short-chain fatty acids cannot be metabolized and processed properly without sufficient levels of this enzyme. As a result, these fatty acids are not converted to energy, which can lead to characteristic features of this disorder, such as lethargy and hypoglycemia. Medium-chain and short-chain fatty acids or partially metabolized fatty acids may build up in tissues and damage the liver, heart, and muscles, causing more serious complications.

This condition is inherited in an autosomal recessive pattern, which means two copies of the gene in each cell are altered. Most often, the parents of an individual with an autosomal recessive disorder each carry one copy of the altered gene but do not show signs and symptoms of the disorder.

Genetics is found to be the cause of enolase deficiency. The individual in the first known case of this deficiency was heterozygous for the gene for β-enolase, and carried two missense mutations, one inherited from each parent. His muscle cells synthesized two forms of β-enolase, each carrying a different mutation. These mutations changed glycine at position 374 to glutamate (G374E) and glycine at position 156 to aspartate (G156D).

Isovaleric acidemia is estimated to affect at least 1 in 250,000 births in the United States.

The fatty acids are transported by carnitine, and defects in this process are associated with several disorders. They involve the step immediately before oxidation, and are often grouped with the oxidation disorders.

The GM1 gangliosidoses (or GM1 gangliosidos"i"s) are caused by a deficiency of beta-galactosidase, with resulting abnormal storage of acidic lipid materials in cells of the central and peripheral nervous systems, but particularly in the nerve cells.

GM1 Gangliosidoses are inherited, autosomal recessive sphingolipidoses, resulting from marked deficiency of Acid Beta Galactosidase.

Typically, initial signs and symptoms of this disorder occur during infancy or early childhood and can include poor appetite, vomiting, diarrhea, lethargy, hypoglycemia, hypotonia, liver problems, and abnormally high levels of hyperinsulinism. Insulin controls the amount of sugar that moves from the blood into cells for conversion to energy. Individuals with 3-hydroxyacyl-coenzyme A dehydrogenase deficiency are also at risk for complications such as seizures, life-threatening heart and breathing problems, coma, and sudden unexpected death.

Problems related to 3-hydroxyacyl-coenzyme A dehydrogenase deficiency can be triggered by periods of fasting or by illnesses such as viral infections. This disorder is sometimes mistaken for Reye syndrome, a severe disorder that may develop in children while they appear to be recovering from viral infections such as chicken pox or flu. Most cases of Reye syndrome are associated with the use of aspirin during these viral infections.

Succinyl-CoA:3-oxoacid CoA transferase deficiency (SCOT deficiency) is an inborn error of ketone body utilization. Succinyl-CoA:3-oxoacid CoA transferase catalyzes the transfer of coenzyme A from succinyl-coenzyme A to acetoacetate. It can be caused by mutation in the "OXCT1" gene.

First described in 1972, more than 30 people have been reported in the medical literature with this inborn error of metabolism. They experience attacks of ketoacidosis during illness, and even when unwell may have elevated levels of ketone bodies in blood and urine (ketonemia and ketonuria, respectively). Not all people with SCOT deficiency have persistent ketonemia and ketonuria, particularly those with milder defects of enzyme activity.

Pyruvate carboxylase deficiency is an inherited disorder that causes lactic acid and to accumulate in the blood. High levels of these substances can damage the body's organs and tissues, particularly in the nervous system. Pyruvate carboxylase deficiency is a rare condition, with an estimated incidence of 1 in 250,000 births worldwide. This disorder appears to be much more common in some Algonkian Indian tribes in eastern Canada.

Transaldolase deficiency is a disease characterised by abnormally low levels of the Transaldolase enzyme. It is a metabolic enzyme involved in the pentose phosphate pathway. It is caused by mutation in the transaldolase gene (TALDO1). It was first described by Verhoeven et al. in 2001.