Nature versus Nurture
The Reich and Lowen tradition emphasizes the role of early experience (nurture) on early development, and de-emphasizes the role of genes (nature). That experiences and not genes literally shape the body is not a popular mainstream belief. Genes probably do play a role in character development--at least it is not presently provable that they do not. Genes are simple time delayed mechanical processes--something has to turn them on and so the causality of even DNA is not fully determined at birth. However, it is a common observation that siblings of the same parents may have very different bodies and characters.
Alexander Lowen was sometimes considered absolutist in the way that he ascribed adult body type to early experience. This is not because he was arguing genes played no role, but rather, neither he nor anyone else, had any way of changing genes. There is no gene therapy for humans even in 2010. The gene therapy that is being worked on is for large discrete aberrations. There is no way of even conceiving of what gene therapy would be for the subtle effects of genes on human suffering and adjustment.
Damaging experience, however, can be prevented in the future, and the effects of past experience can be modified by present experience*. So Reich and Lowen concentrated on what could be reversed. Often the mention of genes arises when one is uncomfortable with the implication that widespread, culturally accepted, and even well-intentioned parenting has been damaging. Also, Lowen insisted that a return to health was accompanied by a change in appearance§, and this is a hard concept for people who feel their appearance has not changed. However, changes in appearance do sometimes happen, and this could not happen if genes prohibited a change in appearance. Also, genetic 'destiny' is often a metaphor for a sense of hopelessness.
*That limitations from past bad experience are so infrequently changed by new good experience has to be conceded, but that is the reason for the intricacy of psychotherapy--a 'corrective' experience may require some knowledge to bring about.
§The change in appearance being considered consists of things like spinal alignment, gait, appearance of eyes and pupils, shape of ribcage, skin tone, radiance, small but noticeable shift in the position of facial bones, etc... Obviously many things like eye and hair color are genetic and not changeable