New research shows that microscopic mites that live in human pores and mate at night on our faces are becoming streamlined creatures due to their unusual lifestyles that may soon become one with humans.
The mite is transmitted during childbirth and carried by nearly every human, peaking in adults as the pores widen. They are about 0.3 mm long, are found in the hair follicles on the face and in the nipples, including the eyelashes, and feed on the natural sebum secreted by cells in the follicles. They become active at night, moving between follicles in search of mating.
First-ever study of the genome sequence of D. marsupial The mites found that their solitary presence and resulting inbreeding leads to rejection of unnecessary genes and cells and a transition towards the transition from ectoparasites to endosymbiotics.
Dr. Alejandra Perotti, associate professor of invertebrate biology at the University of Reading who co-led the study, said: “We found that these mites had a different arrangement of body parts genes than other similar species because they adapted to life protected within the pores. These changes resulted in their DNA. to some unusual characteristics and behaviors of the body.”
In-depth study of Demodex marsupial DNA detection:
- Due to their solitary existence, with no exposure to external threats, no competition to infect hosts, and no encounters with other moths of different genes, genetic reduction made them very simple organisms with small legs supported by only three unicellular muscles. They live on a minimal repertoire of proteins – the fewest seen in this and related species.
- This genetic decline is also the reason for their nocturnal behaviour. The mites lack protection from UV rays and have lost the gene that causes animals to wake up in broad daylight. They are also unable to produce melatonin – a compound that makes small invertebrates active at night – but can feed their nocturnal mating sessions on melatonin secreted by human skin at dusk.
- The unique genetic arrangement also leads to the unusual mating habits of the moths. Their genitals have moved forward and males have a penis that protrudes upward from the front of their bodies which means they have to position themselves below the female when mating, and mate while both cling to human hair.
- One of their genes is reversed, giving them a specific arrangement of oral appendages that protrude further for food gathering. This enhances their survival at an early age.
- Mites have more cells in their early age than they do in adulthood. This conflicts with the previous assumption that parasitic animals reduce their cell numbers early in development. The researchers argue that this is the first step in converting the mites into symbionts.
- The lack of exposure to potential pairs who could add new genes to their offspring may have set the moths on an evolutionary impasse and possible extinction. This has been seen before in bacteria that live in cells, but never in an animal.
- Some researchers have hypothesized that the mites do not have an anus, and therefore must collect all their faeces throughout their lives before releasing them when they die, causing dermatitis. However, the new study confirmed that they do have anus and are therefore wrongly blamed for several skin diseases.
The research was led by Bangor University and the University of Reading, in collaboration with the University of Valencia, the University of Vienna and San Juan National University. It was published in the magazine Molecular biology and evolution†
Dr. “Moths have been blamed for many things,” said Henk Bragg, co-lead author of Bangor University and the National University of San Juan. “Their long association with humans may suggest that they can also play a simple but important beneficial role playing, for example by Keeping the pores in our face closed.”
Material supplied by University of Reading† Note: Content is subject to change according to style and length.