71.   Through natural selection the gene gained in the population because people who had the gene did not succumb to malaria.

72.   Those who have the gene could be targets for special effort to delay puberty by slowing their weight gain and increasing exercise.

73.   He said those who had the gene were not necessarily doomed to face a heart attack.

74.   Both parents had the gene, but in most cases the female gene was silenced during formation of the egg.

75.   Tests are also being developed for people to find out of they have the gene.