In a nutshell, humans with Transhumanist disorder dangerously defy the reality where death is the norm. They also defy what the medical systems consider "natural". Death is composed of causes and conditions that the medical system considers natural. Cancer, heart disease, and other debilitating diseases are considered "natural" if they happen late in life. Transhumanists defy that logic, and think that they should live indefinitely. In addition, there is a desire to not only prolong one's life, but to enhance it with technology, so as to become a superhuman.
Could "Transhumanist Disorder" become a real diagnosis? If the majority of the world were to hear of a minority group of individuals altering their brains and bodies in order to become better than them, would they try be disturbed enough to label it a mental disorder? Might they think that individuals who want to become like Gods to be similar to megalomaniacs? There may very well come a time when Transhumanists are considered insane and dangerous enough to need to be institutionalized and medicated. Sounds horrible.
I think it might be a good idea for Transhumanists to take a good look at themselves and consider if their reality is really ready for everything that they are proposing. If being labeled as "sick" doesn't sound appealing I can understand why, yet isn't the human condition, as it stands rather sick?
For the human, many of manifestations of aging are considered "normal". Transhumanists realize that the so-called "natural causes" that underly the death should be eliminated even if that means converting oneself an unnatural being. To put it simply, the attraction that many Transhumanists feel toward their potential inhuman future-self is disturbing to the average Joe.
Would it be possible for Transhumanists to acknowledge that they are different now, and that they may in fact have some sort of disorder? I mentioned "Transhumanism" to a doctor once and they said that it could be "dangerous". At what point does a DIY Transhumanist end up hurting themselves and marking the movement as being "dangerous"?
Maybe Transhumanists should align themselves with the currently disabled public to advocate for their well being through life enhancing technologies and science from the standpoint that, "we too admit we are disabled". Transhumanists may currently be considered functional human beings by the doctors who examine them, but if it truly pains us to see the lack of acceptance of public support for our cause then we might think of calling ourselves "disabled" now.
By taking the "weaker position", Transhumanists are agreeing with the potential feedback from the world that they may in fact have a problem. This is a humble position. It aligns the Transhumanists with the weak, instead of with the powerful who seek to grow ever more superhuman. Transhumanists needed seperate themselves from the world by proclaiming to be in a "stronger position". It might be advantageous to recognize that we are in a worse off position due to what many consider an impossible dream. That impossible dream, is to become something other than human. It is the realization that ones humanness is disabling for the individual who feels they should be enabled.
It is possible that the human who thinks that they can become something impossible (a posthuman), is worse off than the ordinary person who is happy just as they are. Transhumanism may be an unrealistic and unnecessary burden. That burden is a disorder because it tells the human body that it is not good enough. It is like the person who wants to keep getting plastic surgery again and again and again.