Problem with if/else

You have an additional set of {} between your first if/else statement and the second one.
This should work:

void loop()
{
  if (digitalRead(53) == LOW) {
    digitalWrite(12, HIGH);
    delay(12);
  }
  else {
    digitalWrite(12, LOW);
    delay(12);
  }

  if (digitalRead(49) == LOW) {
    digitalWrite(10, HIGH);
    delay(12);
  }
  else {
    digitalWrite(10, LOW);
    delay(12);
  }
}