Yes it is possible that there is a predisposition for those two as well. If not genetic than something else is at work. This is not to say that we should allow those to take place. Nor does it mean that we should look at homosexuality in the same light. There are key differences of the three, Pedophilia and Bestiality target classes of individuals who are either unable to speak up or "agree" to sex or are to young to fully understand the ramifications of sex. Homosexuality usually is expressed by two homosexuals. Two consenting adults who agree to the relationship (on one level or another). The issue should not be considered in the light of "normal/abnormal" behavior but in the light of 'healthy/unhealthy' behavior. Is someone harmed? Then it is unhealthy. Rather a simple concept, however many will come up with many reasons why homosexuality is harmful - rarely based in logic or upon hard data. Harm of the Soul does not count - there is no evidence of this "soul" people speak of therefore we can not demonstrate that harm to the soul can or does take place. We can, however, demonstrate that children do suffer a wide range of ills triggered by pedophilia. These can be measured, observed and treated. It does suggest that if there is a predisposition for those acts then we must immediately stop imprisoning those who do such and no longer treat them like criminals. We have to come up with a better way to address the issues, one that treats it more like a genetic disorder than a crime. BTW there is strong evidence that most crimes are committed through emotional/mental disorders suggesting that warehousing of individuals as punishment is not the real answer to the problem, that we need instead find a working solution that treats the ills, not punish the patient. Not too long ago people were warehoused for insanities - not treated, imprisoned. Today we know a lot more and have discovered medical treatments that treat the illness. In many cases people who would have been imprisoned (in a house of bedlam) today can lead productive lives due to therapies. We have a long way left to go when it comes to identifying the cause of many things. We are still in the dark about the human mind, how it works and why its at all - we only have thin shadows of theory about the processes. And when it comes to application of these theories we soon discover that individuals can (and often do) live outside of any given theory. Psychology and Psychiatry are relatively new fields of study, having only slipped below the surface with perhaps 500 more years of study before we have a sound working science that can answer all questions. There are still questions. For instance when it comes to homosexuality which does not hurt anyone and is between consenting adults - do we have the right to treat it as a disease or should we consider it to be a disposition for a trait along the lines of skin color, eye color? To really answer that question we have a lot of bias to overcome. And even when hard solid evidence does come to light I assure there will be many who will seek a "cure" to "fix" the problem, even if it is not a problem. As a species we are not ready or able to answer that kind of question rationally and with compassion or with enough understanding of what is "human" and what is "normal" or not. If anyone comments on this part of my answer we will find that there are beliefs and takes on this which do not agree. Demonstrating how unready we really are. There is a slight moral problem when we start treating patients who are predisposed to _______. Many find that they are 'happy' with who and what they are and refuse treatment. However, especially in the mental/emotional areas - often a patient is forced to accept treatment because we have a set of standards which we consider to be "healthy" (sane). When does the right of society overshadow the right of the individual? In some cases their is no black and white answer. We set standards on bestiality and pedophilia based on the "victim" or the individual who is targeted. We can demonstrate in pedophilia that children can suffer greatly from such an experience. so there is good reason to judge these traits as "wrong". Homosexuality on the other hand does not itself lead to harm of individuals, two consenting adults can gain much from such a relationship. Yes homosexuals are prone to self destructive behaviors more than straight people. However the cause is not their homosexuality - the cause is how society and individuals treat them because they are homosexuals. Your question opens a can of worms - in many cases people will refuse to open the can, in some they will open the can and then proceed to set standards which we can not justify on the worms.