According to the Bible/Torah Sarah was Abrahams sister, so does that make Isaac inbred? Are Jews from Isaac?

Genesis chapter 11 says that Sarah was his wife. Abraham lied about Sarah being his wife to the Egyptians, because the Egyptians didn't fear GOD. Lot's daughters because of their disobedience had made their father drunk and slept with him. Their children were Moab, the father of the Moabites, and Benammi, the father of the Ammonites.