D40/KNL1/CASC5 and autosomal recessive primary microcephaly

Area of Science:

• Genetics
• Neurodevelopmental Biology
• Cell Biology

Background:

• Autosomal recessive primary microcephaly (MCPH) is a rare neurodevelopmental disorder characterized by reduced brain size.
• Over a dozen genes (MCPH1-13) have been implicated in MCPH, involving proteins with diverse functions.
• The D40/KNL1/CASC5 gene, initially linked to leukemia and cancer/testis expression, encodes a kinetochore protein crucial for cell division.

Purpose of the Study:

• To review known gene targets responsible for MCPH.
• To summarize clinical studies related to MCPH.
• To detail the molecular and biological aspects of the D40/KNL1/CASC5 gene and its encoded protein in MCPH4.

Main Methods:

• Literature review of studies on MCPH genetics and clinical presentations.
• Analysis of molecular and biological data concerning the D40/KNL1/CASC5 gene and its protein product.
• Synthesis of information on MCPH1-13 gene targets.

Main Results:

• Mutations in the D40/KNL1/CASC5 gene cause MCPH4, a specific form of primary microcephaly.
• The D40/KNL1/CASC5 gene encodes a kinetochore protein essential for mitotic cell division.
• In vivo evidence confirms the critical role of this gene in brain growth, beyond its in vitro and animal model functions.

Conclusions:

• The D40/KNL1/CASC5 gene is a key player in brain development, with mutations leading to MCPH4.
• Understanding the molecular mechanisms of MCPH genes, like D40/KNL1/CASC5, is crucial for neurodevelopmental research.
• This review consolidates current knowledge on MCPH genetics, clinical aspects, and the biology of the MCPH4-associated gene.