Related Experiment Video

Updated: May 29, 2026

Multi-Gene Single Nucleotide Polymorphism Detection in Gastric Cancer Based on Ion Semiconductor Sequencing Platform
06:21

Multi-Gene Single Nucleotide Polymorphism Detection in Gastric Cancer Based on Ion Semiconductor Sequencing Platform

Published on: May 10, 2024

[Homozygous mutation in the intrinsic factor gene in a child with severe vitamin B12 deficiency]

Tina Lund Leunbach1, Preben Johansen, Stephan M Tanner

  • 1Børneafdelingen, Aarhus Universitetshospital, Aalborg Sygehus, 9000 Aalborg, Denmark. tll@rn.dk

Ugeskrift for Laeger
|August 27, 2011
PubMed

Insights

A rare genetic mutation caused cobalamin deficiency in a child, leading to anemia and low blood counts. Hydroxocobalamin injections effectively treated the condition, resolving adverse effects from cyanocobalamin.

Area of Science:

  • Pediatric Hematology
  • Medical Genetics
  • Nutritional Science

Background:

  • Congenital intrinsic factor deficiency is a rare cause of vitamin B12 malabsorption.
  • Early diagnosis and treatment are crucial to prevent severe hematological and neurological complications.

Observation:

  • A 28-month-old boy presented with pallor and weight stagnation, diagnosed with macrocytic anemia and pancytopenia.
  • Genetic analysis revealed a rare homozygous mutation in the intrinsic factor gene, confirming hereditary cobalamin deficiency.
  • The patient's sister exhibited similar symptoms, and their father, a heterozygote, had low cobalamin levels.

Findings:

  • Monthly cyanocobalamin injections, the standard treatment, induced adverse leg cramps in the patient.
  • Switching to monthly hydroxocobalamin injections successfully resolved the anemia and pancytopenia without side effects.
  • Gastroscopy and biopsies showed no pathological findings, ruling out other causes of malabsorption.

Implications:

  • This case highlights the importance of genetic testing for suspected inherited metabolic disorders.
  • Hydroxocobalamin may be a preferable alternative to cyanocobalamin in specific patient populations due to potential adverse reactions.
  • Understanding the genetic basis of cobalamin deficiency informs personalized treatment strategies and family screening.

More Related Videos

Constitutive and Inducible Systems for Genetic In Vivo Modification of Mouse Hepatocytes Using Hydrodynamic Tail Vein Injection09:35

Constitutive and Inducible Systems for Genetic In Vivo Modification of Mouse Hepatocytes Using Hydrodynamic Tail Vein Injection

Published on: February 2, 2018

In Vivo Augmentation of Gut-Homing Regulatory T Cell Induction08:02

In Vivo Augmentation of Gut-Homing Regulatory T Cell Induction

Published on: January 22, 2020

Related Concept Videos

Inborn Errors of Metabolism01:20

Inborn Errors of Metabolism

Phenylketonuria (PKU) is a protein metabolism disorder characterized by high blood levels of the amino acid phenylalanine. This results from a mutation in the gene responsible for phenylalanine hydroxylase, an enzyme that converts phenylalanine into tyrosine. When this enzyme is deficient, phenylalanine builds up in the blood, leading to symptoms such as vomiting, rashes, seizures, growth deficiency, and severe mental retardation. An early diagnosis and a diet restricting phenylalanine intake...
Vitamins01:30

Vitamins

Vitamins, derived from the Latin word for life, are essential organic substances required in small quantities for optimal growth and overall well-being. Unlike other organic nutrients, vitamins don't act as sources of energy or building materials but rather facilitate these nutrients' utilization by the body. Vitamins are predominantly coenzymes, assisting enzymes in specific chemical actions, like the oxidation of glucose for energy involving B vitamins. Most vitamins are not produced in our...
Pedigree Analysis01:35

Pedigree Analysis

Overview
Translation01:31

Translation

Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
Translation01:31

Translation

Lesson: Translation
Translation is the process of synthesizing proteins from the genetic information carried by messenger RNA (mRNA). Following transcription, it constitutes the final step in the expression of genes. This process is carried out by ribosomes, complexes of protein and specialized RNA molecules. Ribosomes, transfer RNA (tRNA), and other proteins produce a chain of amino acids—the polypeptide—as the end product of translation.
Translation Produces the Building Blocks of Life
Role of Vitamins in Maintaining Bone Health01:25

Role of Vitamins in Maintaining Bone Health

The growth and maintenance of bone are regulated by a combination of nutritional factors, including vitamins, such as vitamin A, B12, C, D, and K.
Vitamin A
Vitamin A is involved in the process of bone remodeling. Retinoic acid, the active metabolite of Vitamin A, has nuclear receptors in osteoblasts and osteoclasts, which are involved in bone remodeling.
Vitamin B12
Vitamin B12 acts as a cofactor during the formation of osteoblast-related proteins, such as osteocalcin. Vitamin B12 plays a role...