Non-random fertilization in mice correlates with the MHC and something else

Area of Science:

• Evolutionary biology
• Immunogenetics

Background:

• Sexual reproduction is hypothesized to provide an advantage in host-pathogen coevolutionary dynamics.
• Mate choice and maternal selection may involve the major histocompatibility complex (MHC) due to its role in parasite-host interactions.

Observation:

• The MHC's influence on fertilization, specifically oocyte sperm choice and meiotic division outcome, was investigated.
• In vitro fertilization experiments were conducted using mouse strains congenic for their MHC.

Findings:

• Nonrandom MHC combinations were observed in resulting blastocysts.
• Evidence suggests both oocyte choice and post-fertilization meiotic events contribute to nonrandom MHC combinations.
• The observed patterns in MHC combinations changed over time, indicating external factor influence.

Implications:

• The MHC may play a role in selecting fertilization partners, potentially enhancing offspring immune diversity.
• These findings suggest a more complex role for the MHC in reproduction than previously understood.
• Further research is needed to identify external factors influencing MHC-based fertilization choices.