Tag Archives | Genetics

The Evolution Paradigm Shift

Evolution 21 CenturySuzan Mazur interviews James Shapiro, author of Evolution: A View from the 21st Century, for Counterpunch:

Suzan Mazur: I went through the book over the weekend. It’s very thoughtful the way you’ve put it together. Would you describe your theory, which involves cells speaking to one another — cognitively, informationally. You say in reality the “gene” is “not a definite entity” — it’s “hypothetical in nature.”

James Shapiro: There are three components there.

(1) As I say in the book, cells do not act blindly. We know from physiology and biochemistry and molecular biology that cells are full of receptors. They monitor what goes on outside. They monitor what goes on inside. And they’re continually taking in that information and using it to adjust their actions, their biochemistry, their metabolism, the cell cycle, etc. so that things come out right. That’s why I use the word cognitive to apply to cells, meaning they do things based on knowledge of what’s happening around them and inside of them.

Read the rest
Continue Reading

Natural Selection Driving Human Evolution As Late as the 19th Century

Writes ScienceNow via WIRED Science:

In a world where we’ve tamed our environment and largely protected ourselves from the vagaries of nature, we may think we’re immune to the forces of natural selection. But a new study finds that the process that drives evolution was still shaping us as recently as the 19th century.

The finding comes from an analysis of the birth, death, and marital records of 5,923 people born between 1760 and 1849 in four farming or fishing villages in Finland. Researchers led by evolutionary biologist Alexandre Courtiol of the Institute for Advanced Study Berlin picked this time period because agriculture was well established by then and there were strict rules against divorce and extramarital affairs. The team looked at four aspects of life that affect survival and reproduction, key signposts of natural selection: Who lived beyond age 15, who got married and who didn’t, how many marriages each person had (second marriages were possible only if a spouse died), and how many children were born in each marriage.

Read the rest
Continue Reading

Antibiotic Resistance Genes Accumulating in Lake Geneva Via Wastewater Treatment Plants

Lake Geneva

Photo: Christopher Down (CC)

Via ScienceDaily:

Large quantities of antibiotic-resistant bacteria enter the environment via municipal — and especially hospital — wastewater streams. Although wastewater treatment plants reduce the total number of bacteria, the most hazardous — multiresistant — strains appear to withstand or even to be promoted by treatment processes. This was demonstrated by Eawag researchers in a study carried out in Lake Geneva, near Lausanne.

Treated wastewater from the city of Lausanne — around 90,000 m3 per day — is released into Vidy Bay (Lake Geneva); the discharge point is located 700 m offshore, at a depth of 30 m. The Lausanne region does not have a pharmaceutical industry or intensive animal production. However, the Lausanne treatment plant receives wastewater not only from the region’s 214,000 inhabitants and a number of smaller healthcare centres, but also from a major healthcare facility — the University Hospital of Canton Vaud (CHUV).

Read the rest
Continue Reading

The Inbred Appalachian Family With Blue Skin

bluefamilyA real-life blue-blooded family exists, ironically, in the impoverished hills of Kentucky. As they have mingled with the broader population, the number of blue children has dwindled, sadly. Via Daily Mail:

Dating back to the early 1800s, an isolated family in eastern Kentucky started producing children who were blue. As a result of a coincidental meeting of recessive genes, intermarriage and inbreeding, members of the Fugate family were born with a rare condition that made them visibly discoloured. Looking at the portrait, they appear to have been either Photoshopped, but science proves that the condition is in fact real.

It began when Martin Fugate, a French orphan, settled on the banks of eastern Kentucky’s Troublesome Creek to claim a land grant in the early 19th century. He married a red-haired American named Elizabeth Smith – who had a very pale complexion – and their union formed a genetic mutation that resulted in their descendants being born with blue skin.

Read the rest
Continue Reading

Icelanders Avoid Inbreeding Through Online Incest Database

Ingólfr ArnarsonSo says Samantha Grossman in TIME:

Nowadays, some light Internet stalking is as common a pre-date ritual as showering or putting on a clean shirt. But for Icelanders, that online screening process can include running a date’s name through an incest database.

Sound ridiculous? Consider this: when you live in an isolated nation with a population roughly the size of Pittsburgh, accidentally lusting after a cousin is an all-too-real possibility. But a search engine called Íslendingabók (the Book of Icelanders) allows users to plug in their own name alongside that of a prospective mate, determining any familial overlap. The site claims to track 1,200 years of genealogical information about the island’s inhabitants. Anyone with an Icelandic ID number — that is, citizens and legal residents — is accounted for, the New York Daily News reports.

Not only can the site rule out courtships that might be a bit too close for comfort, but also it helps users determine if they share family ties with any famous Icelanders.

Read the rest
Continue Reading

Rare Mutation Leaves People Without Fingerprints

No PrintsThis would be a useful trait for the aspiring supervillian. Natalie Villacorta wrote recently in Science:

In 2007, a Swiss woman in her late 20s had an unusually hard time crossing the U.S. border. Customs agents could not confirm her identity. The woman’s passport picture matched her face just fine, but when the agents scanned her hands, they discovered something shocking: she had no fingerprints.

The woman, it turns out, had an extremely rare condition known as adermatoglyphia. Peter Itin, a dermatologist at the University Hospital Basel in Switzerland, has dubbed it the “immigration delay disease” because sufferers have such a hard time entering foreign countries. In addition to smooth fingertips, they also produce less hand sweat than the average person. Yet scientists know very little about what causes the condition.

Since nine members of the woman’s extended family also lacked fingerprints, Itin and his colleagues, including Eli Sprecher, a dermatologist at the Tel Aviv Sourasky Medical Center in Israel, suspected that the cause might be genetic.

Read the rest
Continue Reading

All Non-African People Are Part Neanderthal

Neanderthal child

Reconstruction of a Neanderthal child.

Interesting article from Alasdair Wilkins on io9.com:

The evidence has been mounting for years that early humans and Neanderthals interbred, but now it’s pretty much a certainty. Part of the X chromosome found in people from outside Africa originally comes from our Neanderthal cousins.

It’s kind of amazing to think that, as recently as just a few years ago, the scientific consensus was that humans and Neanderthals were completely separate species and probably didn’t interbreed. Since then, a ton of new evidence has come to light to change that position, and now new research from Damian Labuda of the University of Montreal more or less completes this big reversal.

Neanderthals, one of the last extant hominid species other than our own, left Africa somewhere between 400,000 and 800,000 years ago and settled mostly in Europe until they went extinct 30,000 years ago. Early modern humans left Africa about 80,000 to 50,000 years ago, meaning they overlapped with Neanderthals in time and place for at least 20,000 years.

Read the rest
Continue Reading

Meet Kenny, An Inbred White Tiger (Photos)

KennyVia Prose Before Hos:
Kenny is a white tiger ‘selectively’ inbred while in captivity in the United States. As zoo’s and exotic pet stores have increased the demand for white tigers, breeders have attempted to recreate the ideal white tiger — large snout, blue eyes, white fur — through relying on a limited pool of captive white tigers. The result? An astoundingly high rate of deformities and health issues. For example, Kenny is mentally retarded and has significant physical limitations.
Continue Reading

American Parents Submit Kids To DNA Testing

A Single Nucleotide Polymorphism is a change of a nucleotide at a single base-pair location on DNA. Author: David Hall (CC)

A Single Nucleotide Polymorphism is a change of a nucleotide at a single base-pair location on DNA. Author: David Hall (CC)

Call me old-fashioned, but voluntarily submitting your children’s DNA for inclusion in a database seems foolhardy to me. Just how secure is that database? Is Gattica really so far in the future once this becomes the norm? From BBC News:

Parents believe the benefits of testing their children for the genetic risk of some diseases outweigh the negative consequences, according to US scientists.

In the study, published in the journal Pediatrics, parents who were offered a genetic test supported their children also being tested.

The authors say doctors and politicians need to be more aware of the issue. Genewatch UK said children should never be tested for adult conditions.

Genetic testing used to be confined to specialist clinics, but direct-to-consumer testing is now possible. People send a sample to a company in the post and are told if they have any genes which carry an increased risk of illness.

Read the rest
Continue Reading

Twins Mystery In Brazilian Town Solved

15208360Cândido Godói, a Brazilian village with an extreme abundance of blonde twins, has long spawned conspiracy theories. Namely, that infamous Nazi doctor Josef Mengele (who visited repeatedly in the 1960s and treated locals) created an “Aryan twin town.” However, the New York Times reports that scientists have identified a “twins gene” possessed by residents (who are mostly of German descent and have a high rate of inbreeding), likely putting the matter to rest:

For years, so many twins have been born in the small southern Brazilian town of Cândido Godói that residents wonder whether something mysterious lurks in the water, or even if Josef Mengele, the Nazi physician known as the Angel of Death, conducted experiments on the women there.

But a group of scientists now says it can rule out such long-rumored possibilities. Ursula Matte, a geneticist in Porto Alegre, Brazil, said a series of DNA tests conducted on about 30 families since 2009 found that a specific gene in the population of Cândido Godói appears more frequently in mothers of twins than in those without.

Read the rest
Continue Reading