In
my last post, I gave a brief introduction as to what SNPs (single Nucleotide
Polymorphisms) are. Please enjoy this short video to give you a better
understanding of SNPs
Now that you understand what SNPs are, let’s delve a little deeper in to how geneticists look at the DNA during the genetic testing.
SNP Chips
A
sample of the patients DNA must first be taken. This can be done by either a
blood test (usually) or a simple swab of saliva. Once that is done, next the
scientist will use a something called a micro-array chip, or as I like to call
them SNP chips. With these chips, they apply the DNA onto the chip. The strands
of DNA separate, and each segment of DNA has a specific part of the chip that
it will bind to. This is known as hybridization in the world of genetics. Once
the DNA is hybridized to the SNP chip, they will add outside DNA (called
probes) that are tagged with fluorescents. These florescent DNA probes will
bind to the patients DNA if they are complementary. It’s like a game of
playground tag, except the probes can only "tag" DNA that it is
exactly complementary to.
This allows the geneticists to compare DNA between healthy patients and sick ones. Because each segment of DNA has specific spot on the SNP chip, it allows the geneticist to see what part of the DNA is mutated. If someone has a mutation in either the BRCA 1&2 gene, the part of the DNA that has the instructions for those cells will light up a different color than the rest of the DNA.
Here is an example of that:
What Kind of
Genes are BRCA 1&2?
BRCA 1 & 2 are tumor suppressor genes. As
the name suggests, these are genes that help prevent the tumors for growing in
our cells. When a mutation occurs in the instructions of the BRCA 1&2 gene,
it changes how they work. In breast cancer, they are turned off. When they are
turned off, the cell loses its control on growth.
References:
I want a SNPs that can get me curly hair too!!I loved that video. The visuals in that video were great and I thoroughly enjoyed listening to the narrator's English accented voice. I had to rewind from being distracted by it. Your blog was simple and short and very easy to understand and read! I can't wait to learn more!
ReplyDeleteThis video is great. While i was watching it,I was remembering school house rock as a child and how much I learned from that movie. If only everything in college could be taught this way!!. Your blog is a great and concise. And definitely is a good reminder of the bits and pieces we learned in genetics and biochem!
ReplyDeleteMerna, the quality of your presentation is still top-notch. The information on SNP and micro-array chips is easy-to-follow and well-organized. I liked how you've taken liberties to make your own mnemonic: ‘SNP chips.’ The visuals you've selected provided not only a great transition point but also a moment for the reader to internalize the information given. This is a really interesting topic, and I'm curious to see how you approach future chapters.
ReplyDeleteThis is pretty interesting, the video is a unique way to explaining a scientific and a difficult concept. Nonetheless, relating this to Molecular Biology of Cancer, it is intriguing the way you simplified a very complex lab technique. I believe that cancer is considered by the general public as not just an unexplainable birth of a monster, but also a death sentence; however, you explained the science in simple terms and transformed cancer from an evil zombie to a more scientific explanation. Well done, I like the way you are addressing the science and simplified diction. I hope in the future to learn more about the preventive measures when it comes to breast cancer.
ReplyDeleteI love the video! I enjoy everything about this blog. Your blog is simple, short, easy to understand and read. You gave great examples and showed great pictures. I am interested in learning more about this topic and am looking forward to reading more of your blogs! Great job.
ReplyDelete