Also known as, replicons or Low Copy Repeats (LCRs), Segmental Duplications (SDs) are homologous sub-sequences found in eukaryotic genomes, which bear very high sequence similarity of over 95% + are less than 2Mb in length. They are most commonly found in primate and human genomes. Half of the human Y chromosome, for example, consists of SDs.
Charcot-Marie-Tooth (CMT) disease type 1A is genomic disorder resulting in peripheral neuropathy, which is caused by the duplication of a 1.4Mb region in the 17p12 chromosome band. This SD causes the duplication of the gene encoding PMP22, which lies in the centre of the region, and is hypothesised to cause CMT1A.
3. Inoue, K., Dewar, K., Katsanis, N., Reiter, L.T., Lander, E.S., Devon, K.L., Wyman, D.W., Lupski, J.R. and Birren, B., 2001. The 1.4-Mb CMT1A duplication/HNPP deletion genomic region reveals unique genome architectural features and provides insights into the recent evolution of new genes. Genome research, 11(6), pp.1018-1033.