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Reviewed July 2011

What is the official name of the PTS gene?

The official name of this gene is “6-pyruvoyltetrahydropterin synthase.”

PTS is the gene's official symbol. The PTS gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the PTS gene?

The PTS gene provides instructions for making an enzyme called 6-pyruvoyltetrahydropterin synthase. This enzyme is involved in the second of three steps in the production of a molecule called tetrahydrobiopterin (BH4). Other enzymes help carry out the first and third steps in this process.

Tetrahydrobiopterin plays a critical role in processing several protein building blocks (amino acids) in the body. For example, it works with the enzyme phenylalanine hydroxylase to convert an amino acid called phenylalanine into another amino acid, tyrosine. Tetrahydrobiopterin is also involved in reactions that produce chemicals called neurotransmitters, which transmit signals between nerve cells in the brain. Because it helps enzymes carry out chemical reactions, tetrahydrobiopterin is known as a cofactor.

How are changes in the PTS gene related to health conditions?

tetrahydrobiopterin deficiency - caused by mutations in the PTS gene

More than 45 mutations in the PTS gene have been found to cause tetrahydrobiopterin deficiency. When this condition is caused by PTS gene mutations, it is known as 6-pyruvoyltetrahydropterin synthase (PTS) deficiency. PTS deficiency accounts for more than half of all cases of tetrahydrobiopterin deficiency.

Most PTS gene mutations change single amino acids in 6-pyruvoyltetrahydropterin synthase, although some mutations insert or delete small amounts of DNA in the PTS gene or disrupt the way the gene's instructions are used to make the enzyme. Changes in 6-pyruvoyltetrahydropterin synthase greatly reduce or eliminate the enzyme's activity. Without enough of this enzyme, little or no tetrahydrobiopterin is produced. As a result, this cofactor is not available to participate in chemical reactions such as the conversion of phenylalanine to tyrosine. If phenylalanine is not converted to tyrosine, it can build up to toxic levels in the blood and other tissues. Nerve cells in the brain are particularly sensitive to phenylalanine levels, which is why excessive amounts of this substance can cause brain damage.

Additionally, a reduction in 6-pyruvoyltetrahydropterin synthase activity disrupts the production of certain neurotransmitters in the brain. Because neurotransmitters are necessary for normal brain function, changes in the levels of these chemicals contribute to intellectual disability in people with PTS deficiency.

Where is the PTS gene located?

Cytogenetic Location: 11q22.3

Molecular Location on chromosome 11: base pairs 112,226,365 to 112,233,973

The PTS gene is located on the long (q) arm of chromosome 11 at position 22.3.

The PTS gene is located on the long (q) arm of chromosome 11 at position 22.3.

More precisely, the PTS gene is located from base pair 112,226,365 to base pair 112,233,973 on chromosome 11.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about PTS?

You and your healthcare professional may find the following resources about PTS helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the PTS gene or gene products?

  • 6-pyruvoyl-H4-pterin synthase
  • 6-pyruvoyl-tetrahydropterin synthase
  • PTPS
  • PTP synthase
  • sepiapterin synthase A
  • sepiapterin synthesizing enzyme 1

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding PTS?

acids ; amino acid ; cofactor ; deficiency ; disability ; DNA ; enzyme ; gene ; molecule ; neurotransmitters ; phenylalanine ; protein ; toxic ; tyrosine

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.

See also Understanding Medical Terminology.

References (11 links)


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.

Reviewed: July 2011
Published: November 23, 2015