Gul A. et al., Neurogenetics (2006): The Q3180P, identified in family MCP29, is the first non-protein-truncating pathogenic mutation identified in the ASPM gene. In family MCP29, four affected individuals are the results of first-cousin marriage. The severities of the mental retardation of these individuals vary from mild to moderate. These individuals are unable to read or write but can perform basic tasks. Examination of the affected members did not reveal seizures, spasticity, or weakness. Because the clinical features, including sloping foreheads and reduced head circumferences, observed in family MCP29 are similar to those observed in other families linked to MCPH5 locus, it appears that there is no correlation between the mutation and the phenotype