The costs of analyzing DNA have come down significantly over time, so it’s becoming increasingly common to sequence DNA and discover all kinds of biological curiosities. It’s not quite as fast and easy as they make it look on detective shows on TV, but DNA analysis has made some pretty amazing advances. Here are just a few examples of genetic testing that you might have missed.
- It’s actually not that uncommon to find people who are chimeras — individuals with multiple genomes in their bodies. Twins can end up with a mixture of blood types that co-exist in their veins. Nearly all mothers retain some residual fetal cells from their children (and this is a form of microchimerism). We have a lot to learn about the genetic makeup of individuals, and it’s not as simple as one might have assumed. [url]
- The male fetal DNA from a mother’s son can often be found in her brain. Brain autopsies of 59 women showed that the majority of them had male DNA, giving evidence that fetal DNA can not only cross the placenta, but also the blood-brain barrier. [url]
- A blood test can now reliably detect an unborn baby’s gender at just 7 weeks old. The genetic material from the baby can be detected and analyzed, offering some advantages over more invasive tests such as amniocentesis. [url]
I’ve written about some of this but it is always interesting to see what the latest is. Many people are chimeras with different DNA sequences depending on the cells. This can have an impact on forensics.
And the fact that fetal DNA can be detected in women 50 years after they gave birth is really intriguing. ANd if the sex of the baby can be determined at 7 weeks, how soon can a pregnancy at all be determined?