You Inherit Part of Your Fingerprint from Your Parents

2 minute read
Originally posted here: https://mcgill.ca/oss/article/did-you-know/you-inherit-part-your-fingerprint-your-parents

Our fingerprints are a one-of-a-kind pattern, so unique to an individual that even identical twins don’t share them. And yet I’m here to tell you that you inherit part of your fingerprint from your parents. Huh?

If you look closely at your fingerprints, you’ll notice that their patterns are one of three main types: loops, whorls or arches.

If you were to look at your fingerprint under a microscope though you’d see that while the ridges on your fingers follow one of the patterns, there are small variations in them, like breaks, forks and islands.

While the general shape of your fingerprints is heritable, these small details, often called minutiae, are not. Why that is comes down to how fingerprints are formed.

When a fetus is about 7 weeks old, they begin to form pads on their hands and feet called volar pads. These pads only exist for a few weeks, because at around 10 weeks they start to be reabsorbed into the palms of the hands and feet.

Around this time, the very bottom layer of the epidermis begins to form folds due to pressures from the growing skin. These folds are the precursors to your finger ridges, or fingerprints, and the pattern they take depends on how much of the volar pad has been absorbed when they begin to form. If the volar pad is still very present, then you’ll develop a whorl pattern. If the volar pad is partially absorbed, you’ll form a loop pattern, and if it’s almost entirely absorbed, you’ll form an arch pattern.

So how do genetics come into this? Well, the rate of volar pad reabsorption and the specific timing of the creases in the epidermis appearing are genetically linked. However, these events only determine the general shape of the fingerprint. The minutiae are influenced by things such as the density of the amniotic fluid, where the fetus is positioned and what the fetus touches while in utero. Since every fetus will grow in a different environment, their minutiae will differ. Even twins that share a uterus will interact with their surroundings differently. So even if your fingerprint shape matches that of your parents, if you look closer, you’ll see the differences that make your prints uniquely yours.

Did you know that fingerprints aren’t only a human feature? To read about fingerprints in koalas, click here!

Koalas Have Fingerprints Just like Humans

2 minute read
Originally posted here: https://mcgill.ca/oss/article/did-you-know/koalas-have-fingerprints-just-humans

In 1975 police took fingerprints from six chimpanzees and two orangutans housed at zoos in England. They weren’t just looking for a unique souvenir; they were testing to see if any unsolved crimes could be the fault of these banana-eating miscreants.

While these primates ended up being as innocent as they seemed, the police did determine that their fingerprints were indistinguishable from a human’s without careful inspection.

A few years later, in 1996, a different type of mammal came under police suspicions: a koala!

While it makes sense that orangutans and chimpanzees would have fingerprints like us, being some of our closest relatives, koalas are evolutionarily distant from humans. It turns out that fingerprints are an excellent example of convergent evolution, or different species developing similar traits independently from each other.

Another example of convergent evolution is seen in the bony structure supporting both birds’ and bats’ wings.

Fingerprints are thought to serve two purposes. First, they aid in grip, allowing an animal to better hold onto rough surfaces like branches and tree trunks. Second, they increase the sensitivity of our touch and allow us a finer level of perception regarding the textures and shapes of the things we hold.

Why this is useful for humans is obvious. Our hands are made to grasp, hold and manipulate objects. Whether it’s some nuts we foraged for or our Xbox controller, we humans spend all day every day relying on our sensitive sense of touch.

For koalas, it’s not really so different. They are incredibly picky eaters, showing strong preferences for eucalyptus leaves of a certain age. It seems that their fingerprints allow them to thoroughly inspect their food before they chow down.

Police aren’t exactly worried about koala bank robbers, but it is possible that koala fingerprints could be found incidentally at a crime scene and be mistaken for a human’s, making it pretty difficult to find a match.

To read about how fingerprints form, how parts of them are genetic, and why identical twins have different ones, click here!

Is It True That Perfumes Contain Aborted Fetal Tissue?

Originally published here: https://mcgill.ca/oss/article/test-you-asked/it-true-perfumes-contain-aborted-fetal-tissue

A Croatian bishop recently claimed that the flesh of aborted fetuses is being used to make expensive perfumes. While claims that vaccines, foods and anti-ageing creams contain aborted fetus parts aren’t new, applying these claims to perfume is. But just as it is a lie to claim that vaccines contain fetal material, it’s likely a lie to claim that perfume does.

This is not to say that fetal material, specifically fetal cells, do not play a role in the manufacturing of some products. They often do. But it’s not as simple as vaccines containing crushed-up aborted fetuses.

As David Gorski explains for Science-Based Medicine, “fear mongering about ‘fetal parts’ in vaccines is, not surprisingly, a distortion of the real situation, which is that the human cell lines are used to make some vaccines.”

Vaccines require viruses, and viruses have to be cultured in cells, as they cannot reproduce on their own. Those cells don’t have to be human but using animal cells for vaccine development causes some problems. Animals are costly to keep alive, may be infected with viruses that could contaminate vaccines, and don’t grow all viruses well. Animal products like chicken eggs can be used, but then there is a risk that an egg shortage could cause a vaccine shortage.

So, we prefer to use human cells to culture viruses, but where are we sourcing these cells from?

There are two cell lines currently used to develop vaccines. The first, named WI-38, was developed in 1962 from the lung tissue of a fetus aborted at 3 months gestational age. The second, named MRC-5, was developed in 1966 from the lung tissue of a fetus aborted at 3.5 months gestational age.

These cell lines have been propagated, kept frozen and are still used today. For more than 50 years, two abortions have allowed us to make vaccines against hepatitis A, rubella, shingles and other illnesses. It’s estimated that 11 million deaths have been prevented by vaccines made with just the WI-38 cell line.

Eleven million deaths over 50 years prevented by two abortions. That is some terribly impressive math, at least to me.

The abortions in question are so far removed from today’s vaccines that even the Catholic Church deems it allowable to use them.

It’s also important to realize that there is no fetal tissue in vaccines. The viruses needed are grown in these cells, then harvested. The cells themselves are not included in the vaccines. There is fetal tissue used in the manufacturing of some vaccines, but no vaccine has ever contained tissue from aborted fetuses.

What about claims that there are aborted fetus cells in some foods?

The idea that companies like Pepsi and Kraft were using aborted fetuses as flavour additives was popularized by an article on the infamously pseudoscientific site Natural News in 2015. They wrote that some processed foods contained “various flavoring agents manufactured using the tissue of aborted human babies.”

Strictly speaking, this isn’t a lie. But it is a misrepresentation. Senomyx, an American biotechnology company develops flavour enhancers for use in food products. To test these enhancers, they used taste receptors expressed in the HEK 293 cell line, which was generated from the kidney cells of a fetus aborted in 1973.

The situation here is the same as for vaccines. Senomyx uses a cell line generated more than 40 years ago in the manufacturing of their product. No fetal cells were everpresent in the final food products. Even Children of God for Life, a prominent pro-life organization, states on their website, “Do not be fooled, shocked or misled – IT IS ABSOLUTELY NOT TRUE! THERE ARE NO FOOD PRODUCTS CONTAINING ABORTED FETAL MATERIAL – NOR HAS THERE EVER BEEN!”

The situation for anti-ageing creams that are manufactured using cell lines derived from fetuses is essentially the same story, and it is likely that these claims of fetal material in perfumes are the same as well. I say likely because the Croatian Bishop Jezerinac appears to be the only one making the claim that fetuses are being used to make perfume. Since he never names a brand of perfume it’s impossible to substantiate or refute his claims.

No fetuses are aborted for the purposes of making vaccines or face creams. There are protections in place to ensure that those seeking abortions are not influenced by the possible donation of their fetus to science. It is illegal to offer money in exchange for fetal tissue, and it is illegal to even discuss using fetal tissue for research with someone seeking an abortion before they have made their decision to terminate their pregnancy.

It’s understandable why those who oppose abortion would be upset by the use of fetal tissue in research, but human fetal tissue is integral to many of the greatest scientific discoveries of recent history. The use of cell lines derived from aborted fetal tissue is common, effective and necessary, and the vast majority of them are products of abortions that happened before I was even born.

Even if you still oppose the use of fetal tissue in research, I would hope that the possible consequences of not vaccinating yourself or your children would trump your ethical concerns about the methods of vaccine manufacturing. However, If you want to skip on the anti-ageing products due to ethical objections, that is just fine by me.