Cool Science: DNA Fingerprinting

It's kind of weird, but one of my dream jobs (I have many, ranging from stationery designer to CEO. #casual.) would be to work as a medical examiner. Okay, just hold up a sec and actually think about it. Just ignore the dead bodies for a minute and it's actually a super cool job. You get to work with crime and the police department, you get to work with the justice system, you get to work with science. A perfect fit for me! Plus I probably would have a bad bedside manner because I'm grumpy in the mornings. No need for a good bedside manner with dead people! Too far? Sorry.

But I do think the crossroads of science and justice can be really, really interesting, especially for a casual scientist. One common scientific procedure in crime (at least according to Law & Order SVU, which may or may not be my main source for this post) is DNA fingerprinting. 

The science of fingerprinting and classifying finger prints is called dactyloscopy, and I'm really only telling you that because it's a cool word and you can feel intellectual if you casually mention it in conversation. But the actual process of connecting a fingerprint with DNA (your genetic ID) is called electrophoresis. 

Electrophoresis takes place in a bunch of steps. First, DNA is isolated and basically cut in half. Then, little chemicals called restriction enzymes cut up the DNA at certain spots, making a bunch of segments of different sizes. The restriction enzymes cut every person's DNA at different places, making the lengths of segments different in every person.

These segments of DNA are called RFLPs (restriction fragment length polymorphisms)...but they are pronounced like "riff-flips", which is sort of fun. So these RFLPs are put in a gel and a charge is sent through the gel, which makes the RFLPs sort themselves by size. Once dyed, these give a display that can be compared against someone's DNA in a data base. It looks like this.

This chart can also be used to tell someone's maternity or paternity. Each of a person's lines (which represent a RFLP, a segment of DNA) is identical to either their mother's or father's. 

If you're interested in learning more about DNA fingerprinting, here are a few resources:

• DNA Fingerprinting
• A game where you can simulate gel electrophoresis
• More basic info on how it works + applications.

How interesting is forensic science?! And how will you use dactyloscopy and RFLPs in a conversation today?

P.S. My favorite recent science articles and why science means we might replace streetlamps with glowing trees #nbd.

Blog Post Organizer (Printable!) + Genetics 101

In the last few months, I've started getting more organized with my blog. I've been keeping a place in Evernote for post ideas and using Google Calendar to plan posts ahead of time. But what I haven't found a good way to do is organize my ideas for a post ahead of time. Usually when I come up with a post idea, I'll have a couple phrases, bullet points, or pictures in my head that I want to make sure I include. But I tend to write only a proposed title, like "blog planning" in my Evernote. Then, when I go back to write it, I have no idea what I intended to write about.

I made this printable to suit my own needs, but I hope it will help you as well! You can print a bunch of these pages and make a binder of them. Whenever you have an awesome post idea, just pop it on one of these pages with a couple tags to help you organize it and a couple notes on content. When you're ready to write the post, just work through the page and remember to promote it on link-ups and social media. Then you're all done! How about that?!

I also use the tags section to help me organize my post ideas by category. Here on Call Me Sassafras, I blog about design, positivity, productivity, music and science. On every planning sheet, I'll write a broad category along with my other tags. Then I sort them out between those five categories. So when I'm getting ready to crank out a post, I try to look at what I've posted recently. If I've posted a lot about design, I'll look under another category for a post idea. 

That's about it! Feel free to use and share as you please, lovebugs! Just right-click on the image + click 'open in new tab' for the big ol' file. 

I hope that helps y'all organize your blog as much as it has helped me! Now, I get to do my favorite thing everrrrrr--share a science bit! :)

Today, I want to share a little bit about genetics. For every trait that you have (think eye color, blood type, etc), you have two pieces of information called 'alleles'. Each allele is part of a gene. Alleles can be either dominant (shown as R) or recessive (shown as r). In most genes, if you have an R allele and an r allele, you will show the dominant trait--the big R wins out and 'hides' the little r trait. If you have RR or rr, then you will show the respective trait. You get one allele from your mama and one from your dad. This is why you may look more like your mom or your dad but still have the same amount of genetic information from both parents.

So for example, pretend that brown eyes are the dominant trait (remember that's R!) and green eyes are recessive (r!). Pretend that my dad is RR and has brown eyes and my mom is rr and has green eyes. I would have to be Rr because I get one allele from each parent. But, the R allele is dominant. So even though I would be born an Rr, I would have brown eyes like my dad. 

Isn't that cool?! Over the coming days, we'll be talking about genetic disorders like Down syndrome and sickle cell anemia. It's gonna be cool, guys! 

Peace out, nerdballers.