Exam 3 Flashcards
(23 cards)
Organizational Hypothesis
exposure/a lack to testosterone during the prenatal critical periods organizes the brain in a sexual dimorphic way
Activational Hypothesis
exposure to sex steroid hormones at puberty activates brain organization to produce sex dif in behaviour and psych
Organizational/Activational Hypothesis in same-sex orientation
sex-atypical levels of T prenatally result in atypical brain organization that reg sexuality. Also under activation hormones
Congenital Adrenal Hyperplasia (CAH)
women exposed to elevated T levels prenataly due to over-activation of the adrenal gland. Exhibit high levels of gynephilia
Finger length ratios
index finger (2d) compared to ring finger (4d) - 2d/4d
- >1.0 2d is longer than 4d (more estrogen in womb)
- <1.0 2d is shorter than 4d (more T in womb)
Otoacoustic emissions
less exposure to prenatal androgens causes OAE
What controls SO in animals
hypothalamus - medial preoptic area and anterior hypothalamus
oSDN in domestic sheep
oSDN as a biomarker
INAH3 in humans
maternal immune response hypothesis
This hypothesis suggests that a mother’s immune system reacts to male-specific proteins (like NLGN4Y) during pregnancy, leading to an increased likelihood that later-born sons will be homosexual.
This occurs because the mother develops antibodies that target male fetal proteins, potentially affecting brain development.
Microchimerism
Microchimerism is when cells from one individual persist in another individual’s body (e.g., fetal cells remaining in the mother’s bloodstream after pregnancy).
These cells may trigger an immune response in the mother, influencing future pregnancies.
hemolytic disease
A hemolytic disease occurs when a mother’s immune system attacks the red blood cells of the fetus, often due to Rh incompatibility (when the mother is Rh-negative and the baby is Rh-positive).
What is NLGN4Y
NLGN4Y (Neuroligin 4, Y-linked) is a protein found on the Y chromosome that plays a role in brain development and synaptic function.
Since only male fetuses have the Y chromosome, only mothers carrying male fetuses are exposed to this protein.
what is an isoform
An isoform is a slightly different version of a protein, usually caused by alternative splicing of a gene.
For example, NLGN4Y has an X-linked counterpart, NLGN4X, which has a similar function but differs in structure.
What is ELISA
ELISA (Enzyme-Linked Immunosorbent Assay) is a lab test that detects antibodies or proteins in a sample (like blood).
Bogaert et al. used ELISA to measure the levels of antibodies against NLGN4Y in mothers’ blood.
What is the Humoral response
A humoral response is part of the immune system that involves B cells and antibodies rather than direct cell attacks (which is called the cell-mediated response).
What is an Epitope
An epitope is the specific part of an antigen (like NLGN4Y) that an antibody binds to.
The maternal immune hypothesis suggests that mothers develop antibodies targeting NLGN4Y epitopes.
What is Neurexin?
Neurexins are proteins that help form synapses (connections between neurons) in the brain.
Neuroligins (like NLGN4Y) bind to neurexins, helping neurons communicate.
If maternal antibodies interfere with NLGN4Y-neurexin interactions, this could affect brain development in male fetuses.
What is NLGN4X
NLGN4X is the X-linked version of NLGN4Y.
While similar, it has structural differences and does not trigger the same immune response in mothers.
Because females (XX) have only NLGN4X, mothers are not naturally exposed to NLGN4Y unless they carry a male fetus.
Is the term “low-response rams” a misnomer
Yes, it is somewhat misleading because “low-response” suggests a lack of sexual interest in general, but these rams actually exhibited significant levels of “sex-like” behaviors during development.
Bonobo monkey homosexuality
FF known more, rub vulvas together, is seen as more of a social action
Savannah baboon homosexuality
MM fondle each other to show alliance
