Identification of the TTTCA expanded repeats in families affected with ADCME. (A) Schematic representation of exons 4, 5 and intron 4 of the SAMD12 gene. The primer sets P1, R1 and M13 anchor were designed to amplify the TTTTA repeats, whereas, P2, R2 and M13 targeted the TTTCA repeats. (B) Representative images of RP-PCR analysis targeting (TTTCA)_n repeats. The RP-PCR analysis showed the TTTCA repeat expansion in ADCME affected individuals (B.III.19 and D.III.2) whereas, the TTTCA repeats were absent in unaffected individuals from both the families (B.III.17 and D.III.4).