byte op = ops[random.nextInt(ops.length)];
switch (op) {
case Substitution.operator:
Substitution sv = new Substitution();
sv.setPosition(newPos);
sv.setBaseChange(new BaseChange(random.nextInt(4)));
record.getReadFeatures().add(sv);
break;
case Deletion.operator:
Deletion dv = new Deletion();
dv.setPosition(newPos);