Down syndrome (trisomy 21) - causes, symptoms, diagnosis, & pathology

What is Down syndrome (trisomy 21)? Down syndrome is a set of symptoms that arise from a genetic abnormality, in which an individual's cells have an extra copy of chromosome 21. Find more videos at

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100+ komento:

Daniel Cacao
Daniel Cacao:
My sister has Down Syndrome. She can't speak, she has to be held by her hand so she can walk. Millie is the best sister that I ever had, even though she is 11 and i'm 15, i love her and i can't imagine a better sis. If you are mean to her, i'm not your friend.
Mitchell Jenkins
Mitchell Jenkins:
Respect to the homies with extra chromies
My brain is hurting
Rajesh Bazala
Rajesh Bazala:
If you wanted to make another human , first youh'd have to find someone that feels the same way .
Aymax jin
Aymax jin:
God i hate math
Scarlette Marie
Scarlette Marie:
I’m so glad this video was made, I’m doing research on Down syndrome because my baby cousin might have it and I really want to learn more about what it is
Man, as someone fascinated with psychology (and medical stuff in general), thank you for making this video and you deserve so many more subscribers!
Nathalie Grieves
Nathalie Grieves:
Can't watch this its making my brain turn to jelly
Oula Suliman
Oula Suliman:
I loved the video. How elegantly designed and structurally narrated!
We've updated this video! The previous version stated that nuchal translucency via ultrasound is seeing how much "light" passes through the neck. This is technically incorrect, as ultrasound uses reflected sound waves to generate images.
Isabella Charlize
Isabella Charlize:
If you wanted to make another human, first you'd have to find someone that feels the same way.

what a god

Because consent is important above everything else🙂👍🏿
Moez Soliman
Moez Soliman:
Your videos were pivotal for my pharmacy exams preparations. I take my hat off to you, and your great effort and explanation :)
siwar zagrouba
siwar zagrouba:
U saved my exam ! I looked everywhere for an explanation of 21 trisomy when its related to rob trans and u only had the answer.. A perfect n detailed answer.. Keep it forward <3
PastaSauce 7
PastaSauce 7:
Did he ... just say "less cells"?

Im gonna make a human with 1,000,000,000,000 chromosomes
Eugene InLaw
Eugene InLaw:
Mosaic principle is very interesting
Potentially, we can all have down syndrome to some extent
Rohan Shetty
Rohan Shetty:
Thanks a lot man ! you made it pretty easy to understand :)
Darwin Derraco
Darwin Derraco:
if this guy was my clinical instructor, i would definitely pass my subjects with flying colors
Master NP
Master NP:
This just made my exam a lot easier. Thank you
Alan Yu
Alan Yu:
My biology presentation is due in 5 days and I haven't started 😅😅 4 minutes speech and 1 minute video on down syndrome. If anyone can help me please reply
*cant they just take out the extra chromosome*
Great videos! You manage to state the most important facts in a simple-to-understand manner!
Javi González
Javi González:
Amazing video! I'm studying medicine and this helped me a lot
kulbir kaur
kulbir kaur:
nicely explained..thanks
Vidya Deshpande
Vidya Deshpande:
That was really good one n the perfect thing what I wanted to know.
In terms of heart defects, he states between the two atria (producing an ejection systolic murmur) being most common ('usually') but note the most common is an AVSD, which produces a holosystolic of course, along with VSDs
AVSD: 29%
VSD: 21.5%
ASD: 19.9% (EJ murmur)

So you will most likely hear a holosystolic murmur

source for chd prevalence ; Benhaourech, CHD & down syndrome
G S:
Wow! I learned so much new stuff today! Thanks
Ales Amaziɣ
Ales Amaziɣ:
Very well made video, i applaud your efforts and you deserve much more recognition. Keep up the good work, great sir. :) And thank you.
That's it 😕 hmm always thought people with down syndrome where mentally challenged or something. I'm glad I'm more educated
Ahmed Barakat
Ahmed Barakat:
i really rally admire your fancy work , keep going :D
Ulrich Robert Musil
Ulrich Robert Musil:
Great video. As a teacher I would use more colors for the stuff. It would be easier to understand it. I had to stop it once to remember the Chromosom comes from the Sperm. But great video.
Mashael Alansary
Mashael Alansary:
I made it to min 6... then my brain melted out of my ears :S
Sapna Kashyap
Sapna Kashyap:
In Robertsonian translocation ,why sperm carries pair and in disjunction sperm carries only single chromosome?
they showed this video in my school to teach us
( but there was no sound )
Tips Tops
Tips Tops:
Why chromosome 21, 21 stands for what sort of thing for segregation in down syndrome
Raj Beats
Raj Beats:
this track is really 🔥 . i actually produce a lot of similar instrumentals. id be down to work on a record with you - let me know
Sargun Arora
Sargun Arora:
You made it super easy!! Thank you so much
What happens when the chromosomes don't split on the first and second step?
Dark Shadow
Dark Shadow:
Now this is how we should learn
Hannah Polan
Hannah Polan:
This is a really good video. Very clear and easy to follow.
Bill Tull
Bill Tull:
i have some questions, coming up, gene function, not jut about 21
Бусинка Show
Бусинка Show:
Salute! Excellent video turned out! Like put # 37! and we welcome you )
aseel hamza
aseel hamza:
What you Can't understand From books , Can be understood from osmosis <3.
Pavan Prajapati
Pavan Prajapati:
In robertsonian syndrom 21 trysomy occur so 14 cromosome monosomy does not occur with it...
So cromosome are 46 obtain same
very very clearly explained, great channel!
Ol’ Skipper
Ol’ Skipper:
I feel pretty dumb. I’m 13 and only now do I know what it is.
lal Jad
lal Jad:
thank you ,this is awesome :))))
Andy Providence
Andy Providence:
it's been close 6 months getting to know your channel and i must say u have great teaching skills and's really helping me! Really Appreciate!
Crazy Gamer
Crazy Gamer:
What are the chances of a sperm with chromosome 21 fertilising an egg cell with zero chromosome 21? Will the offspring will have any abnormal growth and development?
Kalaiarasi M
Kalaiarasi M:
thank you!! ;)
Julie Betend
Julie Betend:
Thanks a lot for this video !
Brian Maina
Brian Maina:
I don't comment much on YouTube videos but this was fantastic! Very well explained!
Kuba Migdał
Kuba Migdał:
Hi, I was wondering if I could use some of your video in a presentation I have for biology class. I really dig the visualizations and they made a lot of stuff clearer. I will credit the channel of course. Liked and subbed
Mely Lisa
Mely Lisa:
Oh wow this was very informative and interesting..Thank you 😊😊👏👏👍👍
Black Friday
Black Friday:
I already graduated from HS 8 yrs ago and now I understand the explanation more clearly 😂 really. My teacher didn't know how to explain either. So got bad grade, but no regret.
zulaikha sokri
zulaikha sokri:
Thank you!
Shelby W
Shelby W:
Thank you so much for this video! It was very helpful
Amit Giram
Amit Giram:
Thank you team Osmosis for such great videos!
Henrique A.
Henrique A.:
Thank you for the explanation of the Robertsonian translocation!
k. roy
k. roy:
very well explained, thank you!
Sunny SunshineXX
Sunny SunshineXX:
Omg I have a bio test tomorrow all about downs syndrome and have missed so much class time...this really helped thx :)
love your explanation man !!!!!! now i get it
Robyn Dalton beauty fashion lifestyle
Robyn Dalton beauty fashion lifestyle:
you know a lot about Down syndrome and I love that about you and I enjoy watching these kind of videos and I love to see more videos like this because it is educating and helpful and keep up the wonderful work on your videos
this gives my head an owie
Chivi Chivonne SpoōkLe OoF シ
Chivi Chivonne SpoōkLe OoF シ:
The reason I was watching this was because I turned on my tv and it showed things about down syndrome. I was confused when I saw it and I still am. (Maybe worse)
Payal Murmu
Payal Murmu:
So , is it that translocational down syndrome is a kind of functional trisomy ...coz the no. of chromosomes as a whole remains the same but amount of either (21/14) is increased relatively ?
Thanks for the great explanation 😊 was really stuck in it for so many days. You are a saviour❤️🔥
Virendrasingh Baghel
Virendrasingh Baghel:
I have my exam tomorrow this is very useful! Thanks
Ricky Smith
Ricky Smith:
i never asked for this
A normal guy on the internet with a dog
A normal guy on the internet with a dog:
This is to complicated!
Samaa El Meghallawy
Samaa El Meghallawy:
Thank you man <3
Im Falling So Im Taking the Time on My Ride
Im Falling So Im Taking the Time on My Ride:
My head hurts...😨
Mehr maa
Mehr maa:
Love you!
areej alanazi
areej alanazi:
you are great guys .. thank you thank you
so basically saying, find someone with 23 chromosome pairs
Yokesh yoke
Yokesh yoke:
Very helpful thank you so much 😍😍
is it just me or does this guy sound kinda like zach from the try guys
Cathy J
Cathy J:
This helped a lott... THANK YOU :)
Yasmin Araújo
Yasmin Araújo:
What program was used to produce the video?
Joseph Benedict
Joseph Benedict:
karyotyping and NIPTs are natural safeguards, there are still no technologies that can stop genetic abnormalities except CRISPR. 😥
i have to make a presentation on Down syndrome for my child development class and we're presenting next week.... I'm so confused by the three types of down syndrome but this video helped a little
diz zy
diz zy:
This video made me understand
Ellie Robinson
Ellie Robinson:
Just a FYI, simian crease is now referred to as single palmar crease (more medically accurate and also culturally appropriate).
Lg G3
Lg G3:
4:21 "so there are a few ways that this can go DOWN" 😉😉😉
I don't understand this!? I just came here to know what is down syndrome and I didn't know it would be so much
sachit Asethi
sachit Asethi:
If you want to make another human, first you hv to find someone that feels the same way lol😆😆
Mikko Kylmänen
Mikko Kylmänen:
A really nice presentation of the different pathways which can lead to Down. Nice that you included the percentages on them as well; can you recall the sources for that information? :)
jyoti bansile
jyoti bansile:
Amazing explaination thanks Osmosis
Joana Borges
Joana Borges:
Great video and as always the pictures/images/drawings are really good :)
John Snow Kumar
John Snow Kumar:
The Down Syndrome used to be called "China Syndrome" till the end of ww2. The name "Down Syndrome" only started being commonly used from the 1970's onwards. After the release of the movie "China Syndrome" about nuclear power plant accident, that name "China Syndrome" informally ended being used completely to refer to kids with Down Syndrome.
Oscar Ramirez
Oscar Ramirez:
You lost me at the chromosome..
Temporary Bakery
Temporary Bakery:
Can you do a video in Tricuspid Atresia?
\\Cheech Unlimited\\
\\Cheech Unlimited\\:
I have a large gap in between my toes, but its just something that runs in the family. no down syndrome. weird 😕
Mike Black
Mike Black:
I need to know more
Michelle Schu-blacka
Michelle Schu-blacka:
Can't help thinking chromosomes are key factors in this video.
Anonymous #32
Anonymous #32:
@theodd1sout james

Can you explain it more easy xD
my lil bro has Down syndrome, I love him and could never wish for a better brother, he’s always nice and sharing, he doesn’t have friends though and I try to help him make some.
Hussam baj
Hussam baj:
amazing video :) :)
Ketki Mutha
Ketki Mutha:
Superb explaination ❤👍
Pls state more information about treatment and management