Sexual Differentiation: Modifying the Paradigm

Teresa Binstock binstoct at essex.hsc.colorado.edu
Sat Jun 17 16:42:23 EST 1995


Newsgroups: bionet.neuroscience
Subject: Sexual Differentiation: Modifying the Paradigm
Summary: non-gonadal, non-hormonal genomic sex differences
Expires: 
Sender: Teresa Binstock  binstoct at essex.hsc.colorado.edu
Followup-To: 
Distribution: 
Organization: University of Colorado, Health Sciences Center
Keywords: paradigm shift, sexual orientation, gender orientation, vomeronasal
Newsgroups: bionet.neuroscience
Subject: Sexual Differentiation: Modifying the Paradigm
Summary: 
Expires: 
Sender: Teresa C. Binstock via Binstoct at essex.hsc.colorado.edu
Followup-To: 
Distribution: 
Organization: University of Colorado, Health Sciences Center
Keywords: paradigm shift, gender orientation, sexual orientation, vomeronasal
Cc: 
SEX DIFFERENTIATION: MODIFYING THE PARADIGM

The following points are summarized from an abstract and paper entitled 
"Sex Differentiation: Modifying the Paradigm" first presented at the 8th 
Biennial Retreat of the Developmental Psychobiology Research Group of the 
University of Colorado (USA) Health Sciences Center in May of 1994.

The retreat was entitled "Gender Differences in Brain and Behavior", and 
Teresa Christine Binstock is author of and retains copyright to the above 
named abstract and paper. 

MAIN POINTS of the abstract:

I. For many decades the concept "Sexual Differentiation" (SD) has been 
conceived as the equivalent of gonadal/hormonal SD (i.e., g/h-SD).

A. The presumption that SD is the equivalent g/h-SD is erroneous and 
misleading, because there are genomic sex differences (other than lack of 
or presence of SRY) that are neither gonadal nor hormonal.

B. Examples of SD that is neither gonadal nor hormonal nor SRY-related 
include but are not necessarily limited to:
1. alphoid repeat sequences (satellite DNA) of the X and Y chromosomes.
2. within the X,Y pseudoautosomal regions, an RNA protein that is similar 
but different on the X and Y chromosomes.
3. differences in replication timing of the X and Y chromosomes -- i.e., 
among human males, the Y and X chromosomes have replication-timimg patterns 
different from the replication-timing patterns of the active X 
and the inactive X chromosomes in human females.

C. These male/female sex differences exist from the time of conception 
and thus preceed development of the gonadal ridge and are accurately 
described as sex differences which are neither gonadal nor hormonal.

II. For many decades, the vomeronasal organ (VO) in humans has been 
described variously as not existing, so small as to be of little 
importance, and as a mere rudiment of pre-human evolutionary development. 
At least one 1994 neuroanatomy text states "authoritatively" that 
significant VO processing does not occur in humans. 

A. This well established belittling of the human VO is eroneous and 
misleading. 

B. Between 1980 and 1994, various mainstream scientific journals have 
published at least 10 studies documenting aspects of the occurrence, 
ultrastructure, and function of the human VO.

C. The VO is strongly implicated in mammalian responses to sexual 
pheromones emitted by other creatures of the same species.

III. We Repeat: Gonadal/hormonal SD is a subset of SD; some SD is genomic 
and is neither gonadal nor hormonal and even preceeds development of the 
gonadal ridge and thus also preceeds and is more fundamental than 
subsequent hormonally induced SD. 

IV. Although erroneous, the presumptive equating of SD with g/h-SD is 
commonplace. 

A. A misleading SD-paradigm misdirects and biases research.

B. Mistakenly equating SD with g/h-SD leads to misconstructed 
observations, rationales, experiments, and discussions (i) about 
male/female brain differences, and (ii) about possible causes of gender- 
and/or sexual orientation.

C. Mistakenly equating SD with g/h-SD also biases aspects of the Nature 
versus Nurture debate.

V. Similarly, outmoded notions about the human VO wrongfully bias 
research concerning (i) male and female brain function, and (ii) possible 
mechanisms and/or pathogeneses of sexual and/or gender orientation.

VI. Circa 1995 and beyond, ideas about human SD and about 
biological components of gender orientation and sexual orientation are on 
less than solid footing if they fail to consider either the human 
vomeronasal organ or genomic SD which is neither gonadal nor hormonal. 

			Copyright 1994 1995

Citations to support these ideas and, when completed, a newly re-written 
paper on this topic can be obtained from:

Teresa C. Binstock     via Binstoct at essex.hsc.colorado.edu




More information about the Neur-sci mailing list