Here, homozygosity mapping was performed using sequence-tagged site (STS) markers for the genomic loci mainly associated with microcephaly in the Pakistani population at the time: MCPH1 (gene MCPH1 on chromosome 8p23.1), MCPH2 (WDR62 on 19q13.12), MCPH3 (CDK5RAP2 on 9q33.2), MCPH9 (CEP152 on 15q21.1, previously classified as MCPH4), MCPH5 (ASPM on 1q31.3), and MCPH6 (CENPJ on 13q12.12). Here, ASPM is linked to microcephaly.