Link Between Math & Genes

Researchers have discovered an unexpected link between number theory in mathematics and genetics, providing critical insight into the nature of neutral mutations and the evolution of organisms. The team found the maximal robustness of mutations—mutations that can occur without changing an organism’s characteristics—is proportional to the logarithm of all possible sequences that map to a phenotype, with a correction provided by the sums-of-digits function from number theory.


An interdisciplinary team of mathematicians, engineers, physicists, and medical scientists has discovered a surprising connection between pure mathematics and genetics. ThAnd yet, again and again, number theory finds unexpected applications in science and engineering, from leaf angles that (almost) universally follow the Fibonacci sequence, to modern encryption techniques based on factoring prime numbers. Now, researchers have demonstrated an unexpected link between number theory and evolutionary genetics.

Specifically, the team of researchers (from Oxford, Harvard, Cambridge, GUST, MIT, Imperial, and the Alan Turing Institute) have discovered a deep connection between the sums-of-digits function from number theory and a key quantity in genetics, the phenotype mutational robustness. This quality is defined as the average probability that a point mutation does not change a phenotype (a characteristic of an organism).

The discovery may have important implications for evolutionary genetics. Many genetic mutations are neutral, meaning that they can slowly accumulate over time without affecting the viability of the phenotype. These neutral mutations cause genome sequences to change at a steady rate over time. Because this rate is known, scientists can compare the percentage difference in the sequence between two organisms and infer when their latest common ancestor lived.is connection sheds light on the structure of neutral mutations and the evolution of organisms.

Number theory, the study of the properties of positive integers, is perhaps the purest form of mathematics. At first sight, it may seem far too abstract to apply to the natural world. In fact, the influential American number theorist Leonard Dickson wrote “Thank God that number theory is unsullied by any application.”     READ MORE...

An Appetite and Sun Connection

According to recent research from Tel Aviv University, exposure to the sun makes men more hungry but not women. The research, which was conducted using lab models, reveals how the metabolic mechanism is activated differently in men and women. 

According to the researchers, sun exposure in males of both animal species and humans triggers a protein called p53 to repair any DNA damage that may have been done to the skin as a result of the exposure.

Ghrelin, a hormone that increases hunger, is produced by the body in response to the activation of p53. The hormone estrogen prevents the interaction of p53 with ghrelin in females, which prevents the urge to eat after exposure to the sun.

Professor Carmit Levy and Ph.D. student Shivang Parikh of the Department of Human Genetics and Biochemistry at TAU’s Sackler Faculty of Medicine led the groundbreaking study. 

 It was carried out in partnership with numerous Israeli and international researchers, including Tel Aviv Sourasky (Ichilov), Assuta, Meir, and Sheba Medical Centers, as well as Dr. Yiftach Gepner and Dr. Lior Bikovski from TAU’s Sackler Faculty of Medicine and Professor Aron Weller from Bar-Ilan University. 

The study was published in the renowned journal Nature Metabolism.  READ MORE...

New Genetics Research

A photograph of the skeleton of one of the four individuals who we have sequenced who we think is likely to have participated in the migration we detect into southern Britain and to have displaced half the ancestry of the local population. This skeleton was excavated from the site of Cliffs End Farm in Kent. Credit: Wessex Archaeology

Two new studies highlight technological advances in large-scale genomics and open windows into the lives of ancient people.

New research reveals a major migration to the island of Great Britain 3,000 years ago and offers fresh insights into the languages spoken at the time, the ancestry of present-day England and Wales, and even ancient habits of dairy consumption.

The findings are described in Nature by a team of more than 200 international researchers led by Harvard geneticists David Reich and Nick Patterson. Michael Isakov, a Harvard undergraduate who discovered the existence of the migration, is one of the co-first authors.


This image is of bronze age tools from the National Museums of Scotland, which could give readers a sense of the material culture associated with people who lived at the time of the migration. Credit: Bronze Age tools curated the National Museums of Scotland

The analysis is one of two Reich-led studies of DNA data from ancient Britain that Nature published on Tuesday. Both highlight technological advances in large-scale genomics and open new windows into the lives of ancient people.

“This shows the power of large-scale genetic data in concert with archaeological and other data to get rich information about our past from a time before writing,” said Reich, a professor in the Department of Human Evolutionary Biology and a professor of genetics at Harvard Medical School. “The studies are not only important for Great Britain, where we now have far more ancient DNA data than in any other region, but also because of what they show about the promise of similar studies elsewhere in the world.”

The researchers analyzed the DNA of 793 newly reported individuals in the largest genome-wide study involving ancient humans. Their findings reveal a large-scale migration likely from somewhere in France to the southern part of Great Britain, or modern-day England and Wales, that eventually replaced about 50 percent of the ancestry of the island during the Late Bronze Age (1200 to 800 B.C.).

The study supports a recent theory that early Celtic languages came to Great Britain from France during the Late Bronze Age. It challenges two prominent theories: that the languages arrived hundreds of years later, in the Iron Age, or 1,500 years earlier at the dawn of the Bronze Age.  READ MORE...

World's Largest Organism

Aerial outline of Pando, with Fish Lake in the foreground. (Lance Oditt/Friends of Pando)

In the Wasatch Mountains of the western US on the slopes above a spring-fed lake, there dwells a single giant organism that provides an entire ecosystem on which plants and animals have relied for thousands of years. This single genetic individual weighs around 6,000 metric tons. By mass, it is the largest

Although it looks like a woodland of individual trees with striking white bark and small leaves that flutter in the slightest breeze, Pando (Latin for "I spread") is actually 47,000 genetically identical stems that arise from an interconnected root network.  This single genetic individual weighs around 6,000 metric tons. By mass, it is the largest single organism on Earth.

Aspen trees do tend to form clonal stands elsewhere, but what makes Pando interesting is its enormous size. Most clonal aspen stands in North America are much smaller, with those in western US averaging just 3 acres.

Pando has been around for thousands of years, potentially up to 14,000 years, despite most stems only living for about 130 years. Its longevity and remoteness mean a whole ecosystem of 68 plant species and many animals have evolved and been supported under its shade.

This entire ecosystem relies on the aspen remaining healthy and upright. But, although Pando is protected by the US National Forest Service and is not in danger of being cut down, it is in danger of disappearing due to several other factors.  READ MORE...