Faculty Mentor

Dr. Elaine Vanterpool

Files

Download

Download Full Text (740 KB)

Description

HMBS, also known as hydroxymethylbilane synthase, is a gene that is responsible for providing instructions for making the enzyme named hydroxymethylbilane synthase. This enzyme is involved in the creation of a molecule called heme. Heme plays an important part in all of the body’s vital organs. It is important to all organs however, it is most prevalent in the blood, bone marrow, and liver. Heme is essential in making iron-containing proteins called hemeproteins. To produce heme, an eight-step process must occur that requires 8 different enzymes. “Hydroxymethylbilane synthase is responsible for the third step in this process, which combines four molecules of porphobilinogen (the product of the second step) to form a compound called hydroxymethylbilane. In subsequent steps, five other enzymes produce and modify compounds that ultimately lead to heme” When looking at the health conditions related to the genetic changes of heme, it is important to highlight that there have been more than 300 mutations in the HMBS gene. With these mutations, people have been identified with a mutation called porphyria, also known as acute intermittent porphyria. Some of these mutations change single protein building blocks in hydroxymethylbilane synthase. Other mutations add or delete genetic material within the HMBS gene, which can alter the structure and function of the enzyme. Mutations in the HMBS gene reduce the activity of hydroxymethylbilane synthase, which allows compounds called porphyrins to build up in the liver and other organs. These compounds are formed during the normal process of heme production but reduced activity of HMBS. This build-up, in addition to other nongenetic, unhealthy habits, leads to attacks of severe abdominal pain and other symptoms in people with acute intermittent porphyria.

Publication Date

4-1-2025

City

Huntsville

Disciplines

Biology

Comments

Jason Kahari, Student Researcher

Title: An Analysis of HMBS Variants Associated with Acute  Intermittent Porphyria

Included in

Biology Commons

Share

 
COinS