Molecular genetics of human primary microcephaly: an overview

Area of Science:

• Neuroscience
• Genetics
• Developmental Biology

Background:

• Autosomal recessive primary microcephaly (MCPH) is a congenital neurodevelopmental disorder.
• Characterized by a smaller brain size (microcephaly) and non-progressive intellectual disability.
• MCPH is a neurogenic mitotic disorder affecting neuronal precursor cell proliferation.

Purpose of the Study:

• To review the genetic basis and pathophysiology of MCPH.
• To highlight the known MCPH genes and their potential roles in disease.
• To discuss the implications for clinical management and genetic counseling.

Main Methods:

• Literature review of MCPH genetic loci and associated genes.
• Analysis of proposed molecular mechanisms underlying MCPH.
• Synthesis of findings on etiology, pathophysiology, and clinical management.

Main Results:

• Twelve MCPH loci (MCPH1-MCPH12) have been identified, involving genes such as Microcephalin and ASPM.
• Mutations in these genes are predicted to disrupt mitotic spindle orientation, DNA damage response, or centrosomal functions.
• These disruptions lead to reduced neuron production and consequently, microcephaly.

Conclusions:

• Understanding MCPH genetics and pathophysiology aids in clinical management.
• Molecular diagnosis and genetic counseling are crucial for reducing MCPH incidence.
• Further research into centrosomal mechanisms may reveal novel therapeutic targets.