Researchers find genetic 'dial' can control body size in pigs

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Researchers from North Carolina State University have demonstrated a connection between the expression of the HMGA2 gene and body size in pigs. The work further demonstrates the gene's importance in body size regulation across mammalian species, and provides a target for gene modification.

"Essentially, HMGA2 is a gene that controls the total number of cells that an animal has," says Jorge Piedrahita, the Randall B. Terry Distinguished Professor of Translational Medicine and Director of the Comparative Medicine Institute at NC State. "The gene is only active during fetal development, and 'programs' in the number of cells that the animal will be able to generate. When the animal is born, it will only be able to grow to the size dictated by the number of cells that it can produce."

Researchers had previously studied the HMGA2 analogue in mice, which have two different (HMGA2 and HMGA1) involved in body size and body mass index determination. Pigs and humans share the HMGA2 gene responsible for growth regulation in their species. The NC State study looked at size in that expressed both copies of the gene, one copy, or neither copy.

"We found that the amount of the gene expressed is proportional to the size of the animal," Piedrahita says. "If both copies were expressed the pig was 'normal' sized. If one copy was expressed the pig was roughly 25 percent smaller than normal, and if neither copy was expressed the pig was 75 percent smaller.

"The animals grow and develop normally, although the boars with both copies of the gene deleted were sterile. Overall, it seems that controlling the expression of HMGA2 is like using a dial to control ."

The researchers also found that the deletion of HMGA2 affected the resources that the pig fetuses received in utero. In litters containing fetuses with both copies of the gene deleted and fetuses with one or more copy of the gene expressed, the fetuses with both copies deleted did not survive the pregnancy. However, if the litter only contained fetuses with both copies deleted, the fetuses survived and developed normally.

The research appears in Proceedings of the National Academy of Sciences.

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More information: Jaewook Chung el al., "High mobility group A2 (HMGA2) deficiency in pigs leads to dwarfism, abnormal fetal resource allocation, and cryptorchidism," PNAS (2018).
Citation: Researchers find genetic 'dial' can control body size in pigs (2018, May 7) retrieved 21 October 2019 from
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May 07, 2018
So... you could make pigs the size of mice and pigs the size of elephants? How about sharks the size of whales? Lions the size of house cats? Amoebae the size of poached eggs?

How soon before entrepreneurs get their hands on this tech? How soon before these creations find their way into the everglades?

How soon before this planet becomes unlivable? How soon before we can establish underground colonies on mars where isolation can be enforced and runaway creations such as this can be prevented from spreading?

Isolation - the key to our survival.

May 07, 2018
Isolation was the key to evolution here on earth when the oceans, topography, and climate differences kept ecosystems separate. But this is no longer possible with modern transportation.

And without isolation there is no way to prevent universal contamination and pandemic, unless we begin living underground HERE, or on some other planet with surface and groundwater conditions that prevent migration.

And even underground here on earth is there any way to truly isolate?

May 07, 2018
Its very interesting that the movie that is headed to being the highest-grossing flick of all time is about a villain who succeeds in depopulating the entire universe by 1/2. When was the last time we heard of this?

"Stasinos, poet (lived 776 – 580 BC)
"There was a time when the countless tribes of men, though wide-dispersed, oppressed the surface of the deep-bosomed Earth, and Zeus saw it and had pity and in his wise heart resolved to relieve the all-nurturing Earth of men by causing the great struggle of the Ilian war, that the load of death might empty the world. And so the heroes were slain in Troy, and the plan of Zeus came to pass."

"Utnapishtim recounts how a great storm and flood was brought to the world by the god Enlil, who wanted to destroy all of mankind for the noise and confusion they brought to the world. But the god Ea forewarned Utnapishtim, advising him to build a ship..." epic of gilgamesh

-Overpopulations a bitch. Only a movie though, right?

May 07, 2018
Go to GOOGLE IMAGES & Search for Pygmies !
In African short stature is very tied to heredity, but there is much mixing of populations. In Central Africa populations, a region of chromosome 3 is associated with Pygmies. One of these genes is DOCK3 that is part of the genetic makeup of Pygmies and other short non Africans. Another gene CISH inhibits a receptor for growth hormone and is related to immune responses. Another gene variant is HESX1 that is related to anterior pituitary that produces growth hormone. Entirely different genetic mechanisms with different regions of genetic changes are related to short stature in Uganda.

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