metousiosis:

ScienceDaily (Sep. 3, 2009) — Scientists at the Gladstone Institute of Cardiovascular Disease (GICD) have traced the evolution of the four-chambered human heart to a common genetic factor linked to the development of hearts in turtles and other reptiles.

The research, published in the September 3 issue of the journal Nature, shows how a specific protein that turns on genes is involved in heart formation in turtles, lizards and humans.

“This is the first genetic link to the evolution of two, rather than one, pumping chamber in the heart, which is a key event in the evolution of becoming warm-blooded,” said Gladstone investigator Benoit Bruneau, PhD, who led the study. “The gene involved, Tbx5, is also implicated in human congenital heart disease, so our results also bring insight into human disease.”

From an evolutionary standpoint, the reptiles occupy a critical point in heart evolution.

That’s damn interesting! (Although I already knew it before.)

The genome sequencing company Illumina has just delivered the results of a complete human genome sequencing to a customer.

An interesting post. Worth a read.

Here’s the quote from the paper…

Background

From Paleo-Indian times to recent historical episodes, the Mesoamerican isthmus played an important role in the distribution and patterns of variability all around the double American continent. However, the amount of genetic information currently available on Central American continental populations is very scarce. In order to shed light on the role of Mesoamerica in the peopling of the New World, the present study focuses on the analysis of the mtDNA variation in a population sample from El Salvador.

Methodology/Principal Findings

We have carried out DNA sequencing of the entire control region of the mitochondrial DNA (mtDNA) genome in 90 individuals from El Salvador. We have also compiled more than 3,985 control region profiles from the public domain and the literature in order to carry out inter-population comparisons. The results reveal a predominant Native American component in this region: by far, the most prevalent mtDNA haplogroup in this country (at ~90%) is A2, in contrast with other North, Meso- and South American populations. Haplogroup A2 shows a star-like phylogeny and is very diverse with a substantial proportion of mtDNAs (45%; sequence range 16090–16365) still unobserved in other American populations. Two different Bayesian approaches used to estimate admixture proportions in El Salvador shows that the majority of the mtDNAs observed come from North America. A preliminary founder analysis indicates that the settlement of El Salvador occurred about 13,400±5,200 Y.B.P.. The founder age of A2 in El Salvador is close to the overall age of A2 in America, which suggests that the colonization of this region occurred within a few thousand years of the initial expansion into the Americas.

Conclusions/Significance

As a whole, the results are compatible with the hypothesis that today’s A2 variability in El Salvador represents to a large extent the indigenous component of the region. Concordant with this hypothesis is also the observation of a very limited contribution from European and African women (~5%). This implies that the Atlantic slave trade had a very small demographic impact in El Salvador in contrast to its transformation of the gene pool in neighbouring populations from the Caribbean facade.

(via cromagnon)

(From Kambiz Kamrani.)

(The other famous gene being involved with language is FOXP2.)

If there is a genetic basis to Monogamy^[1] (in humans), it makes you wonder… well, makes me wonder at least… if there’s the potential that Monogamy could be breed out of human populations. And if there’s a potential, are there any signs today which makes it seem like it could be happening.^[2]

From a genetics point-of-view, from what I’ve read, it is easier for loss of function or exaggeration and redirections of functions to occur than to develop wholly new complex adaptations. As an example of that — as an example of what loss of function looks like — when comparing wolves to dogs we see that [m]ale wolves help care for their offspring, but male dogs do not.^[3] Then if we believe that Monogamy is a complex adaptation, then it would lead us to believe that it is easier for Monogamy to be lost than for it to re-evolve from scratch.

[1] Because people can mean different things when they say “monogamy”, to be explicit, what I referring to when I say “monogamy” is, when a male and a female live together, have sex with one another, and cooperate in acquiring basic resources such as food, clothes, and money. Often they also care for and raise offspring to together.

[2] Just to be explicit, I’m a fan of Monogamy.

[3] Even though male dogs don’t care for their offspring, I wonder if the “wiring” for that behavior is still there. But if it’s just kind of muted. And thus, would you really have to re-evolve that behavior from scratch.

You have to pay to read this article. Although, I think there’s a free version of the article here.

Here’s a quote…

Variants in just three genes acting in different combinations account for the wide range of coat textures seen in dogs — from the poodle’s tight curls to the beagle’s stick-straight fur. A team led by researchers from the National Human Genome Research Institute (NHGRI), part of the National Institutes of Health, reports these findings today in the advance online issue of the journal Science. “This study is an elegant example of using genomic techniques to unravel the genetic basis of biological diversity,” said NHGRI Scientific Director Eric Green, M.D., Ph.D. “Genomics continues to gain new insights from the amazing morphological differences seen across the canine species, including many that give clues about human biology and disease.”

[…]

Modern dog breeds are part of a unique population structure, having been selectively bred for many years. Based on this structure, the researchers were able to break down a complex phenotype — coat — into possible genetic variations. “When we put these genetic variants back together in different combinations, we found that we could create most of the coat varieties seen in what is among the most diverse species in the world — the dog,” Dr. Ostrander said. “If we can decipher the genetic basis for a complex trait such as the dog’s coat, we believe that we can do it as well with complex diseases.”

Specifically, the researchers found an alteration in the RSPO2 gene that results in wiry hair that grows in a pattern that gives the dogs a mustachioed look with long details called furnishings. Examples of dogs with wiry coats are Scottish terriers, Irish terriers and schnauzers. Long hair that is silky or fluffy was linked to a variant in the FGF5 gene. Cocker spaniels, Pomeranians and long-haired Chihuahuas are examples of dogs with long coats. A variant in the KRT71 gene produces curly coated dogs, such as the Irish water spaniel. Finally, if all three variants are present, a dog has a long and curly coat with furnishings. Examples of this type of breed include poodles and Portuguese water dogs.

“We don’t yet know the precise roles, if any, of these three genes in the variety of hair textures seen among humans,” Dr. Ostrander said. The FGF5 (long hair) gene and KRT71 (curly) gene have been found to affect hair in mice and cats in addition to dogs, so humans may be included as well. The RSPO2 gene has not been previously identified to influence hair texture in mammals, but it does belong to a pathway that has been associated with a coarse hair type found in some people of East Asian ancestry.

As Jason Malloy puts it….

Overcoming bacterial defences allows the genome of one bacteria to be transplanted into another species – creation of synthetic life possible ‘in a month’, claims genome pioneer

(H/T Jason Malloy)