DJ-Men have XY chromosomes. If on the X there is genetic information to deal with fighting infections damage on that one X chromosome may mean men are more likely to get more infected/have less defenses. (Women have XX chromosomes-if one X does have a problem the other X can deal with that.) 

[url]https://jamanetwork.com/journals/jama/fullarticle/2768926[/url];

Key Points

Question  Are genetic variants associated with severe coronavirus disease 2019 (COVID-19) in young male patients?

Findings  In a case series that included 4 young male patients with severe COVID-19 from 2 families, rare loss-of-function variants of the X-chromosomal TLR7 were identified, with immunological defects in type I and II interferon production.

Meaning  These findings provide insights into the pathogenesis of COVID-19.

Importance  Severe coronavirus disease 2019 (COVID-19) can occur in younger, predominantly male, patients without preexisting medical conditions. Some individuals may have primary immunodeficiencies that predispose to severe infections caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Objective  To explore the presence of genetic variants associated with primary immunodeficiencies among young patients with COVID-19.

Design, Setting, and Participants  Case series of pairs of brothers without medical history meeting the selection criteria of young (age <35 years) brother pairs admitted to the intensive care unit (ICU) due to severe COVID-19. Four men from 2 unrelated families were admitted to the ICUs of 4 hospitals in the Netherlands between March 23 and April 12, 2020. The final date of follow-up was May 16, 2020. Available family members were included for genetic variant segregation analysis and as controls for functional experiments.

Exposure  Severe COVID-19.

Main Outcome and Measures  Results of rapid clinical whole-exome sequencing, performed to identify a potential monogenic cause. Subsequently, basic genetic and immunological tests were performed in primary immune cells isolated from the patients and family members to characterize any immune defects.

Results  The 4 male patients had a mean age of 26 years (range, 21-32), with no history of major chronic disease. They were previously well before developing respiratory insufficiency due to severe COVID-19, requiring mechanical ventilation in the ICU. The mean duration of ventilatory support was 10 days (range, 9-11); the mean duration of ICU stay was 13 days (range, 10-16). One patient died. Rapid clinical whole-exome sequencing of the patients and segregation in available family members identified loss-of-function variants of the X-chromosomal TLR7.