sexual original is a sink of genetic variatio in grandfather
y_chromosome is sex_chromosome. oligodactyly is genetic_disease. fertile_animal is sexually_mature_thing. xy is sex_chromosome. oligodactyly is not genetic_disease. genetic_arrhythmia is not genetic_condition. syphilis is sexually_transmitted_disease. genetic_arrhythmia is genetic_condition. isogamy is sexual_reproduction.