People born with heart problems, actually do have a defect in their heart. They could die or have a limited life, because of the defects in their heart. Homosexuals, bisexuals, and asexuals are completely healthy people, whom other than sexual preference are indistinguishable form heterosexuals.
If you took even the slightest amount of time to read some of the theories as to why people are gay, you'd have the answers you're looking for.
Also, for someone who talks about logic like they know a thing or two, you're prone to an awful lot of logical fallacies. Argument from Incredulity, begging the question, fallacy of the single cause, using a single authority, moving the goalposts.... I could go on, but until you have some understanding of why your arguments suck, there's really no point. But then again, bigots usually suck at arguing.
Here's some more evidence that helps refute your stance.
Bearman and Brückner (2002) criticized early studies of concentrating on small, select samples[SUP][7][/SUP] and non-representative selection of their subjects.[SUP][8][/SUP] They studied 289 pairs of identical twins (monozygotic or from one fertilized egg) and 495 pairs of fraternal twins (dizygotic or from two fertilized eggs) and found concordance rates for same-sex attraction of only 7.7% for male identical twins and 5.3% for females, a pattern which they say "does not suggest genetic influence independent of social context."[SUP][7][/SUP]
A 2010 study of all adult twins in Sweden (more than 7,600 twins)[SUP][9][/SUP] found that same-sex behavior was explained by both heritable factors and individual-specific environmental sources (such as prenatal environment, experience with illness and trauma, as well as peer groups, and sexual experiences), while influences of shared-environment variables such as familial environment and societal attitudes had a weaker, but significant effect. Women showed a statistically non-significant trend to weaker influence of hereditary effects, while men showed no effect of shared environmental effects. The use of all adult twins in Sweden was designed to address the criticism of volunteer studies, in which a potential bias towards participation by gay twins may influence the results;
Biometric modeling revealed that, in men, genetic effects explained .34.39 of the variance [of sexual orientation], the shared environment .00, and the individual-specific environment .61.66 of the variance. Corresponding estimates among women were .18.19 for genetic factors, .16.17 for shared environmental, and 64.66 for unique environmental factors. Although wide confidence intervals suggest cautious interpretation, the results are consistent with moderate, primarily genetic, familial effects,
and moderate to large effects of the nonshared environment (social and biological) on same-sex sexual behavior.[SUP][9][/SUP]