Week 10

Hello everyone! I hope everyone had a wonderful week!

So, today marked my last day on site! I can’t believe SRP are basically over :(

This week, I spent a good chunk of my time on site working on my presentation and finalizing all the details of the variant study! While working on my presentation, I found myself wanted to talk about all the rare diseases I had seen, the neurological tests, and the course of treatment. But, since my research was only specific to one person, I had to limit that and talk about the one patient in lots of detail.

Aside from getting the chance to see so many rare neurological disorders, I think my favorite part of this internship was how interactive I got to be with some of the patients. Whether it was playing with a child while Dr. Narayanan talked to the parent about their problem, or holding a puppet elephant to help test for eye movement, I was able to engage the patient while helping in the evaluation process.

My main goal with this internship was to experience what it was like to work in a doctor's office and learn about how genetics and genetic testing can be used to make personalized treatment plans for each patient. I have truly enjoyed every part of this SRP process!

I’m planning on continuing working with Dr. Narayanan during the summer and will continue learning about the process of exome sequencing! But, a huge thank you to you guys for reading my blog every week (and complimenting my gifs)!

Here's another cute gif! See you guys next week for my final post!

Week 9

Hello hello everyone! Week 9. Wow, can't believe that happened so quickly!

So, this week on Monday I shadowed Dr. Narayanan as usual but on Wednesday Dr. Narayanan and I sat down and discussed the details of the case of the boy I am following.

But, before I get into the details of the patient I am following, I wanted to go into a little more detail about how exome sequencing is actually done. First, the DNA has to be prepared (for lack of a better way to say it). The whole gene first has to be transcribed from DNA to hnRNA. hnRNA is heterogeneous nuclear RNA which contains both the transcribed exons and introns and is considered a precursor to mRNA. hnRNA has both transcribed versions of introns and exons, but exome sequencing only looks at the exons in a gene, so the hnRNA is then translated into mRNA. During this translation, the introns are spliced by snRNPs, which are small nuclear ribonucleoprotein particles (which are made of complexes of snRNA and proteins). Since the introns are spliced out, the resulting strand is just made of exons. Then once there is this strand of exons, an exome library is created. After the library is created, computers do their fancy technology stuff and give you a variant file.

Ok, so the variant file is a super super filtered down version of each specific gene that could potentially be disease causing. For example, if in a certain race a disease has a frequency of over 3%, it is not considered to qualify as a rare so it’s thrown out and not shown on the variant file. The variant file is organized by gene name, what type of mutation it is, and whether it comes from the mother or the father of the child. This is all told by what chromosome it is found on, which happens to be another wonderful feature of this huge excel spreadsheet. The one for the patient I am following has over a 1000 rows to look through and identify a possible variant.

So, this took me a little while to wrap my head around, and I'm still trying to understand all the little details about it. Next week, I am going to talk to Dr. Narayanan more about the steps for looking through the sequenced data and how variants can be prioritized. But, that’s all I have for you guys this week! Can't believe projects are almost over :( Here's a cute dog and baby gif though!