New Gut Discoveries (or old ones rediscovered)

Gut Decision: Scientists Identify New Organ in Humans

A mighty membrane that twists and turns through the gut is starting the new year with a new classification: the structure, called the mesentery, has been upgraded to an organ.

Scientists have known about the structure, which connects a person's small and large intestines to the abdominal wall and anchors them in place, according to the Mayo Clinic. However, until now, it was thought of as a number of distinct membranes by most scientists. Interestingly, in one of its earliest descriptions, none other than Leonardo da Vinci identified the membranes as a single structure, according to a recent review.

In the review, lead author Dr. Calvin Coffey, a professor of surgery at the University of Limerick's Graduate Entry Medical School in Ireland, and colleagues looked at past studies and literature on the mesentery. Coffey noted that throughout the 20th century, anatomy books have described the mesentery as a series of fragmented membranes; in other words, different mesenteries were associated with different parts of the intestines.