Complex sentence: Through rumors circulated that the white minis carried defective or lethal genes similar to the blue merle dogs or white boxers and that the white miniature schnauzers have medical problems and deafness, the truth is the white minis have no different health problems than their colored counterparts.
Split into simpler sentences: Through rumors circulated that the white minis carried defective or lethal genes similar to the blue merle dogs or white boxers and that the white miniature schnauzers have medical problems and deafness. The truth is the white minis have no different health problems than their colored counterparts.