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Updated: Jun 5, 2026
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Detection of Small GTPase Prenylation and GTP Binding Using Membrane Fractionation and GTPase-linked Immunosorbent Assay
Published on: November 11, 2018
Rac GTPases in human diseases.
Sung-Yun Pai1, Chaekyun Kim, David A Williams
1Division of Hematology/Oncology, Children's Hospital Boston, Dana-Farber Cancer Institute, Harvard Stem Cell Institute, Harvard Medical School, Boston, MA USA.
Disease Markers
|December 24, 2010
Summary
Mutations in the RAC2 gene cause a severe immune deficiency in infants. This condition, similar to leukocyte adhesion deficiency (LAD), is proposed to be classified as LAD type IV.
Area of Science:
- Molecular biology
- Immunology
- Cellular biology
Background:
- Rho GTPases, part of the Ras superfamily, control diverse cellular functions.
- While implicated in human diseases, only RAC2 mutations cause a specific immunodeficiency.
- This condition presents as severe phagocytic immunodeficiency with life-threatening infections in infancy.
Purpose of the Study:
- To review Rho GTPases, focusing on Rac GTPases.
- To discuss the distinct and shared roles of Rac2 in blood cells.
- To propose a new classification for RAC2-mutation-induced disease.
Main Methods:
- Review of existing literature on Rho GTPases, Rac GTPases, and related genetic deficiencies.
- Analysis of phenotypes from mouse knock-out models (Rac1, Rac2, Rac3).
- Comparison of RAC2 deficiency phenotype with leukocyte adhesion deficiency (LAD).
Main Results:
- The phenotype of RAC2 deficiency in humans mirrors findings in Rac2-deficient mice.
- The RAC2 deficiency phenotype resembles leukocyte adhesion deficiency (LAD).
- Understanding of Rac2's unique and overlapping roles in blood cells has advanced.
Conclusions:
- RAC2 mutations lead to a severe phagocytic immunodeficiency.
- The condition caused by RAC2 mutations shares characteristics with LAD.
- RAC2 mutations causing disease should be termed Leukocyte Adhesion Deficiency type IV (LAD IV).
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