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FECH

FECH

Reviewed July 2009

What is the official name of the FECH gene?

The official name of this gene is “ferrochelatase.”

FECH is the gene's official symbol. The FECH 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 FECH gene?

The FECH gene provides instructions for making an enzyme known as ferrochelatase. This enzyme is involved in the production of a molecule called heme. Heme is vital for all of the body's organs, although it is most abundant in the blood, bone marrow, and liver. Heme is an essential component of iron-containing proteins called hemoproteins, including hemoglobin (the protein that carries oxygen in the blood).

The production of heme is a multi-step process that requires eight different enzymes. Ferrochelatase is responsible for the eighth and final step in this process, in which an iron atom is inserted into the center of protoporphyrin IX (the product of the seventh step) to form heme.

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

porphyria - caused by mutations in the FECH gene

More than 110 mutations in the FECH gene have been identified in individuals with a form of porphyria called erythropoietic protoporphyria. A mutation in one copy of the FECH gene reduces each cell's production of ferrochelatase by about half. However, this is not enough to cause the signs and symptoms of porphyria; people with this disorder must also inherit a second altered copy of FECH. In some affected individuals, the second copy of the FECH gene is also nonfunctional, and cells make almost no ferrochelatase. In other affected individuals, the second copy of the FECH gene retains some of its function. This version of the gene is described as a low-expression allele. It reduces, but does not eliminate, the amount of ferrochelatase produced within cells. A combination of two mutated copies of the FECH gene in each cell, or one mutated copy of the gene and one low-expression allele, is necessary for erythropoietic protoporphyria to develop.

A shortage of functional ferrochelatase allows compounds called porphyrins to build up in developing red blood cells. These compounds are formed during the normal process of heme production, but reduced activity of ferrochelatase allows them to accumulate to toxic levels. The excess porphyrins can leak out of developing red blood cells and be transported through the bloodstream to the skin and other tissues. High levels of these compounds in the skin cause the oversensitivity to sunlight that is characteristic of this condition. Large amounts of porphyrins in the gallbladder can also cause gallstones. Less commonly, a buildup of these compounds in the liver can result in liver damage.

Where is the FECH gene located?

Cytogenetic Location: 18q21.3

Molecular Location on chromosome 18: base pairs 57,544,840 to 57,586,736

The FECH gene is located on the long (q) arm of chromosome 18 at position 21.3.

The FECH gene is located on the long (q) arm of chromosome 18 at position 21.3.

More precisely, the FECH gene is located from base pair 57,544,840 to base pair 57,586,736 on chromosome 18.

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

Where can I find additional information about FECH?

You and your healthcare professional may find the following resources about FECH 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 FECH gene or gene products?

  • Ferrochelatase, mitochondrial
  • ferrochelatase (protoporphyria)
  • Heme Synthetase
  • HEMH_HUMAN
  • Porphyrin-Metal Chelatase
  • Protoheme Ferro-Lyase

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 FECH?

allele ; atom ; bone marrow ; cell ; enzyme ; gallbladder ; gene ; heme ; hemoglobin ; inherit ; iron ; molecule ; mutation ; oxygen ; porphyrin ; protein ; protoheme ; toxic

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

See also Understanding Medical Terminology.

References (13 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 2009
Published: October 27, 2014