From the first sentence: "because of random mutations that become more numerous with advancing paternal age". From the sixth paragraph: "The research team foun

From the first sentence: "because of random mutations that become more numerous with advancing paternal age". From the sixth paragraph: "The research team found that the average child born to a 20-year-old father had 25 random mutations that could be traced to paternal genetic material. The number increased steadily by two mutations a year, reaching 65 mutations for offspring of 40-year-old men."