Related Experiment Video
Updated: Oct 14, 2025
06:21
Author Spotlight: Genetic Profiling for Fluorouracil Response in Gastric Cancer
Published on: May 10, 2024
897
ABCB6 polymorphisms are not overly represented in patients with porphyria
Colin P Farrell1, Gäel Nicolas2,3, Robert J Desnick4
1Division of Hematology, Department of Medicine, University of Utah School of Medicine, Salt Lake City, UT.
Blood Advances
|November 1, 2021
Summary
Genetic factors influence porphyria, but ABCB6 transporter protein genotype does not correlate with disease severity in acute hepatic porphyria or erythropoietic protoporphyria. Therefore, ABCB6 genotyping is not recommended for these conditions.
Area of Science:
- Biochemistry
- Genetics
- Molecular Biology
Background:
- Acute hepatic porphyrias (AHP) and erythropoietic protoporphyria (EPP) exhibit autosomal dominant inheritance with variable clinical penetrance.
- Genetic factors beyond specific enzyme mutations are suspected to influence porphyria phenotype.
- The role of the transporter protein ABCB6 in porphyria pathogenesis and phenotypic heterogeneity remains unclear.
Purpose of the Study:
- To investigate the proposed association between ABCB6 genotype and porphyria phenotype.
- To determine if ABCB6 genotype correlates with disease severity in patients with AHP and EPP.
Main Methods:
- Analysis of a large patient cohort with acute hepatic porphyria and erythropoietic protoporphyria.
- Genotyping of the ABCB6 transporter protein.
- Correlation analysis between ABCB6 genotype and clinical disease severity.
Main Results:
- ABCB6 genotype did not show a significant correlation with disease severity in patients studied.
- Previous findings suggesting a link between ABCB6 and porphyria phenotype were not supported in this cohort.
Conclusions:
- ABCB6 genotype does not appear to be a significant determinant of clinical phenotype or disease severity in acute hepatic porphyria and erythropoietic protoporphyria.
- Routine genotyping of ABCB6 is not warranted for patients diagnosed with AHP or EPP.
Related Concept Videos
01:31ABC Transporters: Exporter
5.3K
ATP-binding cassette or ABC transporter is the largest superfamily of integral membrane proteins. The transporters have transmembrane-binding domains (TMDs) and nucleotide-binding domains (NBDs). The TMDs are specific to their substrates, whereas the NBDs are similar to engines that complete ATP hydrolysis to complete the substrate transport. They can be full transporters consisting of two TMDs and NBDs, half transporters with one TMD and NBD, while some encoded with a single TMD or NBD are...
5.3K
01:22Effect of Hepatic Disease on Pharmacokinetics: Pathophysiologic Assessment and Liver Function Test
22
In clinical practice, the direct measurement of hepatic blood flow to evaluate liver function presents significant challenges due to the intricate and specialized nature of the necessary techniques. Consequently, healthcare professionals often rely on empirical estimates derived from thorough patient examinations and liver function tests to gauge liver health. Among the tools at their disposal, the Child–Pugh and MELD scoring systems stand out for their ability to categorize and assess...
22
01:19Phase I Reactions: Oxidation of Aliphatic and Aromatic Carbon-Containing Systems
384
Phase I biotransformation reactions are integral to drug metabolism, predominantly involving oxidative, reductive, and hydrolytic transformations. Chief among these are oxidative reactions, which enhance the hydrophilicity of xenobiotics and introduce polar functional groups to facilitate their elimination from the body.
Oxidation reactions are fundamental in aromatic carbon-containing systems. An example is the hydroxylation of phenobarbital, a process that transforms it into...
Oxidation reactions are fundamental in aromatic carbon-containing systems. An example is the hydroxylation of phenobarbital, a process that transforms it into...
384
01:08Effect of Hepatic Disease on Pharmacokinetics: Dose Adjustments Due to Hepatic Impairment
25
Hepatic impairment, characterized by decreased liver function, does not uniformly mandate adjustments in drug dosage. Whether dosage modifications are necessary depends on various factors related to the drug's metabolism and elimination pathways. If a drug is primarily excreted via the kidneys and bypasses significant hepatic processing, if it undergoes minimal metabolic transformation in the liver, or if it is volatile and primarily expelled through the lungs, dose adjustments may not be...
25
01:27ABC Transporters: Importer
3.0K
ATP-binding cassette or ABC transporters are a class of ATP-driven pumps that hydrolyze ATP to move solutes across the membrane. They can be grouped into importers and exporters. While exporters are present in all domains of life, importers exist only in bacteria and some plants.
In bacteria, based on the number of transmembrane helices and the chemical nature of their substrates, the ABC importers can be divided into three types:
In bacteria, based on the number of transmembrane helices and the chemical nature of their substrates, the ABC importers can be divided into three types:
3.0K
01:19Allosteric Proteins-ATCase
6.0K
Binding sites linkages can regulate a protein's function. For example, enzyme activity is often regulated through a feedback mechanism where the end product of the biochemical process serves as an inhibitor.
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...
Aspartate transcarbamoylase (ATCase) is a cytosolic enzyme that catalyzes the condensation of L-aspartate and carbamoyl phosphate to N-carbamoyl-L-aspartate. This reaction is the first step in pyrimidine biosynthesis. UTP and CTP, the end products of the pyrimidine synthesis...
6.0K