Intestinal methanogenesis in primates--a genetic and evolutionary approach

Area of Science:

• Microbiology
• Primate Biology
• Genetics

Background:

• Intestinal methanogens are found in many vertebrates, but their presence in primates is not solely linked to diet or morphology.
• Phylogenetic factors, rather than diet, primarily influence methanogen occurrence in primate hindguts.
• Methanogen absence in some New World monkeys suggests hereditary rather than environmental influences.

Purpose of the Study:

• To investigate the factors limiting methanogen occurrence in primate hindguts.
• To determine the inheritance pattern of methane emission in human populations.
• To explore the specificity of the primate-methanogen symbiotic relationship.

Main Methods:

• Phylogenetic analysis of methanogen distribution in primate species.
• Breath analysis of methane occurrence in 56 individuals across 5 human families.
• Comparison of methanogen presence with morphological, physiological, and ethological characteristics.

Main Results:

• Methanogen presence in primates is phylogenetically restricted, with exceptions noted in Old-World monkeys and frequent absence in certain New World monkeys.
• Methane emission in humans was studied in 56 individuals, with results suggesting it segregates as an autosomal dominant trait.
• The findings support a highly specific symbiosis between primates and methanogenic bacteria.

Conclusions:

• Methanogen colonization in primate hindguts is likely influenced by hereditary predisposition and specific host-microbe interactions.
• A specific receptor for methanogenic bacteria may facilitate their persistence in the primate hindgut.
• The study highlights the genetic basis of methanogen symbiosis in primates and humans.