Sequence from two representative cell lines. (Left) Cell line 9072 (DQ4, DQB1*0402, DQCAR117); (right) cell line 9062 (DQ1, DQB1*0603, DQCAR103). The left arrow points to the A nucleotide interrupting the CA repeat sequence in the DQ1 cell line. Note the tetramer GCAA between the (CA)n region and the (GA)5 in the DQ4 cell line. The right arrow points to the G substitution in the flanking region, characteristic of DQCAR103 and DQCAR107. Sequence of opposite strand confirmed the results in both cases (not shown). Sequence was performed as detailed in Methods.