Pulsed-field gel electrophoresis for DXZ4. Southern blot analysis of DNA from 27 individuals from the African population, digested with EcoRI and separated by pulsed-field gel electrophoresis, and hybridized with the probe for the X chromosomal MSR DXZ4. The vertical lines distinguish the nine father-child-mother trios. Trio 5 (family Y077) shows the daughter inheriting her longest DXZ4 array (288 kb – 93 units) from father and the maternal X chromosome containing a shorter array (202 kb – 64 units). Besides the two parental arrays, a third fragment (asterisk) with lower signal intensity was observed, indicating a mitotic instability of the DXZ4 repeat leading to mosaicism where 8% of the cells contained a shorter DXZ4 array (86 kb – 25 units) than those inherited from the parents. Trio 8 (family Y071) illustrates that DXZ4 is a very polymorphic MSR, where the father had a DXZ4 array composed of 120 units and the mother two DXZ4 arrays of 63 and 48 units, respectively. The marker is indicated on the left and right side of the blot.
Schaap et al. BMC Genomics 2013 14:143 doi:10.1186/1471-2164-14-143