int deletionPosition = var.getPosition() - 1;
leftBases = leftBases.subList(0, deletionPosition);
rightBases = rightBases.subList(deletionPosition, rightBases.size());
leftScores = leftScores.subList(0, deletionPosition);
rightScores = rightScores.subList(deletionPosition, rightScores.size());
AlignmentBlock left = AlignmentBlock.getInstance(getChr(), block.getStart(),
leftBases.toByteArray(new byte[leftBases.size()]),
leftScores.toByteArray(new byte[leftScores.size()]));