OH BOY OH BOY.
I just got the results back from my class' foray in sequencing fish samples. ARE YOU READY? They're a mind-bender. https://twitter.com/AwesomeBiota/status/1112846560335880192

Josue sequenced some red snapper. I put money on that being tilapia and...I was right. Someone owes me $5.
His lab partner, Juanni, sequenced Atlantic Salmon. Comes back as Rainbow trout. Unsurprising. Not the same species AT ALL, but unsurprising.

David and Nicolas both sequenced what they thought was Steelhead trout (aka Rainbow trout). David's was smoked, Nic's not.

Nic's was rainbow trout.

David's was coho salmon.

Reena sequenced what was labelled (on the box I bought at the grocery store, no less) Icelandic Cod (MSC-certified).
It was. Thank God.

Sydney sequenced what was labelled (again, ON THE BOX purchased at the grocery store) Pacific Cod.
It was Atlantic Cod. (CRINGEEEE!!!!!!)

Jade sequenced what the sushi restaurant (who shall remain nameless...it's probably not their fault) called red tuna.

IT WAS TILAPIA!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Moe sequenced one of the two samples (from different restaurants) labelled "white tuna". Often another name for albacore tuna.
It was yellowfin tuna. (NOT the same species!! A trade upwards)

Evalyne sequenced the other sample of "white tuna". That was the one that I brought in, that I theoretically would have eaten if I actually liked and ate "white tuna" (I think it's gross).
It was escolar.

THIS IS DANGEROUS. Can cause extreme gastrointestinal distress.

Last but not least of successful sample runs, we had one that makes my skin crawl. It was a sequence that came back with a bunch of "unknown bases" (a bit of cleaning up will help immensely) but I worked with what I had and ran it through the database. Was *supposed* to be Salmon

This salmon was not from a restaurant, but was instead purchased from the seafood department of a local grocery store. Again, to remain nameless. This was purchased from a counter, someone reaches in and grabs the fish, puts it in a bag, sticks a sticker on it, pay by the pound.

Of a gene approximately 650 base pairs long, I was hoping to get a workable sequence of at least 500 base pairs. This one only had 200 clean pairs before I go through the file to improve the sequence generated. So short compared to expected of "working material".

Ready?

Body louse.

I think I might vomit in my mouth a little.
I hope this is a mistake. HOPE TO ANY GOD FROM ANY RELIGION that this is a mistake.

I hope that this somehow becomes a fish sequence when I clean it up a bit. BUT BODY LOUSE.

This wasn't a piece of garbage from a market. This was from a "salmon fillet" that someone paid good money for, cut some off before they cooked it, put it in saran wrap & brought it in.

BODY LOUSE.

Think about how much there must be in that sample to override fish DNA!

Anyway, I don't know if any of my students are nearly as enthralled as I am about the results of this experiment. I'M THRILLED.

16 students, 13 decent bands on the gel.
Of those, we had 9 with pretty decent sequences. THAT'S NOT BAD.
Of those 9, TWO WERE LABELLED CORRECTLY.

So if you "are what you eat" and you like seafood? You have no idea what you are because nothing is labelled properly. If you want to know what you're eating? Make sure it's from a certified sustainable fishery. They know what they're fishing, and know what they're doing.