I found the hypothesis proposed by Dr. Meglathery https://www.rccxandillness.com/ — and I think many of the findings presented today begin to support it.

Co-inherited gene mutations of the RCCX module may explain presence of clusters of genetic illness in families and individuals involving hypermobility/fibrosis (TNXB gene), chronic medical illness (CYP21A2 gene, i.e. EDS-HT, CFS/ME, FM, POTS, MCAS, etc.), psychiatric illness (CYP21A2 gene) and autoimmune diseases (C4 gene).
CYP21A2 gene mutations could confer a stress vulnerability for the development of chronic medical illness (EDS-HT, CFS/ME, FM, POTS, MCAS, etc.) via “21hydroxylase overwhelm” and via PTSD-wiring from CAPS (CYP21A2 Mutation Associated Neuropsychiatric Spectrum) plus negative events.
CYP21A2 gene mutations create a hormone milieu which could affect the developing brain, making it a “brain wired for danger” by age 5, also known as CAPS (CYP21A2 Mutation Associated Psychiatric Spectrum).
CAPS likely predisposes to 4/5 of the major psychiatric illnesses (anxiety disorders, mood disorders, attentional disorders, autism spectrum). Both “21hydroxylase overwhelm” and PTSD wiring associated with CAPS could cause stress-induced mitochondrial shutdown (Naviaux MD PhD).