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Inherited disorder characterized by coloboma,
microcephaly, porencephaly, and hydronephrosis, in which an affected
individual has a head circumference less than 3 standard deviations below
the ageand sex-related mean. All affected individuals are mentally
retarded.
++
Primary Autosomal Recessive Microcephaly; MCPH
Syndrome.
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Approximately 1:250,000 live
births. True microcephaly is inherited as an autosomal recessive trait. It is
genetically heterogenous, with at least five loci mapped: MCPH1 to
chromosome 8p23; MCPH2 to locus 19q13.1-q13.2; MCPH3 at 9q34; MCPH4 at
15q15-q21; and MCPH5 to 1q31, which is a mutant of the ASPM (abnormal
spindle-like, microcephaly associated) gene.
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Microcephaly with sloping forehead, narrow
forehead, and flat occiput. It is associated with mental deficiency and
seizures. A small but apparently normally formed brain is the reason for the
reduced head circumference.
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There are no specific considerations reported.
Assessment of severity of seizures and knowledge of treatment.
Pattison L, Crow YJ, Deeble VJ, et al: A fifth locus for primary
autosomal recessive microcephaly maps to chromosome 1q31.
Am J Hum Genet 67:1578,
2000.
[PubMed: 11078481]