During egg development, meiosis is blocked at prophase I until ovulation. Most instances of nondisjunction maternal occur during prophase I not during meiosis II as noted in the video. Meiosis II occurs following fertilization. Therefore, it occurs right before conception not during embryogenesis. The second issue is picture of the translocation. Non-classical Down syndrome is associated with a Robertsonian translocation not a reciprocal translocation as illustrated in the figure. Chromosome 14 and 21 are acrocentric chromosomes meaning that they have very tiny short arms. The short arms are both lost in a reciprocal translocation and both long arms are connected by the “new” centromere. While these changes are unlikely to impact most people’s understanding of the topics, they could cause problems for some going into selected medical professions. Thank you!
I really loved this video! I too post videos in support of our Down Syndrome toddler only to spread awareness, cause when we discovered we were blessed with a trisomy21 child we were clueless on expectations and who or where to turn to for guidance and support. I subscribed to your channel to demonstrate support. Great Video!
there is also mosaicism :D But- OMG! You're such a life saver! I have spent hours trying to wrap my head around translocation. Awesome video- subscribed! :D
As I begin to do research on down syndrome, and as I do understand that down syndrome is caused by a random error in cell division that results in the presence of an extra copy of chromosome 21, I am driven to a possible solution that this can be averted or overturned by a change in the acid or alkaline levels during the growth in the womb. Each of the 23 chromosome must have a slight difference in chemical structure by analysis, and by associated stages of growth, should be able to be treated as to configure and maintain normal health values in all the variations. If the blood test does not exist then one must be created by which the fetus can be tested and treated. This would be crucial to diagnose and treat many of the prebirth diseases. Thank You!
Thank you . But i do not understand why the number of eggs is four ? I thought that the resulting of miosis one is two cells , one of them (first polar body) does not divide and another can divide to give two cells too , one of them (second polar body) and the another is the ovum , so the result is just one cell ( the ovum ) , right ?
Hello! Just wanted to say, your channel is amazing! And also, thank you for explaining what Down Syndrome is. I have to make presentation about Down Syndrome for my school, and I did not known much about it. So i watched your video, downloaded it and put some subtitles. Soon I will be showing that to my professor, If you are fine with that! Cheers, and thanks for a great video! :)
AK LECTURES Presentation was phenomenal, my professor was amazed and I got an A! :) Thanks and have you ever thought of doing something about Edwards syndrome? :)
Just one correction - at metaphase II the chromatids are no longer sister chromatids due to prophase I crossing over, other than that great explanation
what if Mom had 2 copies of chromosome 21 and this egg is fertilized by a normal sperm. How many copies of chromosome 21 would be in the resulting zygote? and in each cell of the embryo that developed from this zygote?
Excellent presentation up to the part concerning translocation. At that point, it is correct for the most part, but I can't say it's exactly how it goes in real life. Also, the proper naming, Robertsonian translocation, was not there, making grasping of the concept a bit confusing.
I believe that Robertsonian Translocation is what will cause Down Syndrome in this circumstance. Typically, as I understand it, the short arms of the affected acrocentric chromosomes (13, 14, 15, 21, or 22) join together (and are usually lost) while the two long arms fuse together. The short arms contain redundant information, so this isn's significantly expressed, but the addition of a 21 long arm onto the long arm of a 14, for example, means that a child inherit an extra 21 (piggybacked on the 14) along with another normal 14 and a normal set of 21's. In that case the child would have three parts of a 21 (even though they may still have the normal 46 total chromosomes) and would have Down Syndrome. In the drawing, it looks like the short arm is attaching to an entire chromosome, instead of the long arms fusing as I believe is the case in reality. That is why, at first glance, it doesn't look like a typical Robertsonian Translocation. I think this was probably just to maintain simplicity in the illustration.
Im confused my book says that translocation is 45 chromosomes you only have 1 chromosome 21 and at 14 you have that is normal and a bigger one that fused with the 21 son is larger and if you google a karyotype that is exactly what it shows so.... ether you made a mistake or what you are talking about is another form?
Urgent!! My sister is pregnant. She Has 23 weeks of Pregnancy. She has a boy of 8 years old who has cerebral lesion. Now the doctors said to her that the baby inside her belly has a reciprocal translocation in the chromosomal 18 and 21. You think this baby will have any problem? Where She lives there is not any technology to help her more. Can you tell me please. We are devastated. And the doctors said that she need to have an abortion. Please help. Maybe this baby is healthy and they commit an error
1/232 value of down's syndrome ,so i got through amniocentesis.what do you think.my age is 35.my first two babies are normal.too upset n waiting for results.plz reply
I have to like see this a hundred times and I still don't get it. At what point exactly do cells reproduce, when does disjunction take place, is is like happening all the time. Sorry, totally daft and ignorant
During egg development, meiosis is blocked at prophase I until ovulation. Most instances of nondisjunction maternal occur during prophase I not during meiosis II as noted in the video. Meiosis II occurs following fertilization. Therefore, it occurs right before conception not during embryogenesis.
The second issue is picture of the translocation. Non-classical Down syndrome is associated with a Robertsonian translocation not a reciprocal translocation as illustrated in the figure. Chromosome 14 and 21 are acrocentric chromosomes meaning that they have very tiny short arms. The short arms are both lost in a reciprocal translocation and both long arms are connected by the “new” centromere.
While these changes are unlikely to impact most people’s understanding of the topics, they could cause problems for some going into selected medical professions.
Thank you!
I learned more with your video than with my teacher! And english is not even my native language. Thank you so much!
Seriously, this is the video I needed , very in-depth clarity . Thanks for this❤
You explain very well
Elvings92 thank you ! :)
Thank you. I can’t skip one of your video without putting like at the end. As always Informative and to the point 👍🏼👍🏼
I really loved this video! I too post videos in support of our Down Syndrome toddler only to spread awareness, cause when we discovered we were blessed with a trisomy21 child we were clueless on expectations and who or where to turn to for guidance and support. I subscribed to your channel to demonstrate support. Great Video!
Amazing, Thank you. I don't know how you do it but it just clicks when you explain it.
I learn something more today, which I was barely known about yesterday. thank you.
You're a freaking teacher superhero!
Thnks sir .....nice presentation esp on translocation
there is also mosaicism :D But- OMG! You're such a life saver! I have spent hours trying to wrap my head around translocation. Awesome video- subscribed! :D
Sarah Red thanks for subbing!
AK LECTURES is it unbalanced or balanced translocation.
@@Doc_MMJan all translocation are balanecd
Thank you very much for this video. I've been trying to clearly understand this concept for a couple of days now, and you tied it together very well!
Thank you for your explanations. You explained this concept very well!
I could listen to you all day!
have been reading the whole time trying to understand the concept but didn't really, but thank you for this video. I really understood the concept.
As I begin to do research on down syndrome, and as I do understand that down syndrome is caused by a random error in cell division that results in the presence of an extra copy of chromosome 21, I am driven to a possible solution that this can be averted or overturned by a change in the acid or alkaline levels during the growth in the womb. Each of the 23 chromosome must have a slight difference in chemical structure by analysis, and by associated stages of growth, should be able to be treated as to configure and maintain normal health values in all the variations. If the blood test does not exist then one must be created by which the fetus can be tested and treated. This would be crucial to diagnose and treat many of the prebirth diseases. Thank You!
Great work, you deserve many more views!
thehydroman3 thanks, i appreciate that! :)
you tied it all together !
Awesome videos...thank you for uploading
THANKYOUUUUUU IT REALLY HELPS U R SO PROFESSIONAL AT EXPLAINING STUFF
You are great, I'm from Mexico, I don't speak very well English, but I really understand this video, I thanks
you are genius,, thank you indeed... simple and confident presentation.
I follow your lectures always, so great lectures
Thank you for a very simple to understand explanation.
RAMON NUNEZ You're welcome :)
Thank you . But i do not understand why the number of eggs is four ? I thought that the resulting of miosis one is two cells , one of them (first polar body) does not divide and another can divide to give two cells too , one of them (second polar body) and the another is the ovum , so the result is just one cell ( the ovum ) , right ?
Easy to understand. Thank you 😊
Thank you so much! I'll make sure to share your videos with my friends!!
Hello! Just wanted to say, your channel is amazing! And also, thank you for explaining what Down Syndrome is. I have to make presentation about Down Syndrome for my school, and I did not known much about it. So i watched your video, downloaded it and put some subtitles. Soon I will be showing that to my professor, If you are fine with that! Cheers, and thanks for a great video! :)
Milica Sixx Yes, thats fine! Good luck on your presentation! Let me know how it turns out :)
AK LECTURES Presentation was phenomenal, my professor was amazed and I got an A! :) Thanks and have you ever thought of doing something about Edwards syndrome? :)
Milica Sixx Oh nice! Congratulations on the good grade :-) No I have not but perhaps I will sometime in the future.
since yesterday, I was looking for this, finally, I get what exactly the translocation between chromosome 21 and 14 is, thank youuuuuuuuuu a lot
same here
very well explained. i will be ready for spontaneous questions from teacher if i remember everything! thks!
Passed Biochemistry because of you. Now Genetics ! You should do Embryology too !
Finally I got it !! Thanks man, you explain in a great clear way :) :)
you are really really good! please add more and more videos this is really helping me a looooooT!!! Thank you very much dude!
thank you 🥺🌹🌹🌹
great video!!! Thank you !!
wow nice sets of lectures....thanks a lot.
Is it balance or unbalanced translocation.
Thanks so much. I bounded to Ace my presentation tomorrow
Love you man! Keep em' coming plz!
Beautifully narrated the topic, but How the parents have other children's are normal in some cases?
very explicit. It is of great help to me
You are super great! Much appreciated 😍☺️
Just one correction - at metaphase II the chromatids are no longer sister chromatids due to prophase I crossing over, other than that great explanation
This is amazing. You are great!!! SUBSCRIBED! :D
Liban Mohamed Thanks! Appreciate it!
best tutorial about this topic in You tube ! keep it up :)
what if Mom had 2 copies of chromosome 21 and this egg is fertilized by a normal sperm. How many copies of chromosome 21 would be in the resulting zygote? and in each cell of the embryo that developed from this zygote?
thanks mate
You saved my life. :D
great explanation.
well explained...thank you sir
Clear explanation!
Excellent presentation up to the part concerning translocation. At that point, it is correct for the most part, but I can't say it's exactly how it goes in real life. Also, the proper naming, Robertsonian translocation, was not there, making grasping of the concept a bit confusing.
brilliant! thank-you
Thank you.
Thank you very very much!!!!!!
Great video, thanks for the upload.
helpful video
great video !
Thank you
13/5/2019????....thank you sir you
thanks,great sir
Thank you..
Superb!
thanks so much!
goes into translocation very late (when the title says translocation)
How bout it's pathophysiology?
I don't like how this guy speaks at all, but pretty decent video
Amazing😊
What happens if a sperm cell combines with aneuploid egg cell number 1?
thanks sir
Sir ...genetical problems passing in babies at pregnancy time ...?
Is that Robertsonian Translocation?
I believe that Robertsonian Translocation is what will cause Down Syndrome in this circumstance. Typically, as I understand it, the short arms of the affected acrocentric chromosomes (13, 14, 15, 21, or 22) join together (and are usually lost) while the two long arms fuse together. The short arms contain redundant information, so this isn's significantly expressed, but the addition of a 21 long arm onto the long arm of a 14, for example, means that a child inherit an extra 21 (piggybacked on the 14) along with another normal 14 and a normal set of 21's. In that case the child would have three parts of a 21 (even though they may still have the normal 46 total chromosomes) and would have Down Syndrome. In the drawing, it looks like the short arm is attaching to an entire chromosome, instead of the long arms fusing as I believe is the case in reality. That is why, at first glance, it doesn't look like a typical Robertsonian Translocation. I think this was probably just to maintain simplicity in the illustration.
can mosaic down syndrome be diagnosted by cvs (colonal villus sampling)?
Thank youuu🤗
Im confused my book says that translocation is 45 chromosomes you only have 1 chromosome 21 and at 14 you have that is normal and a bigger one that fused with the 21 son is larger and if you google a karyotype that is exactly what it shows so.... ether you made a mistake or what you are talking about is another form?
Urgent!! My sister is pregnant. She Has 23 weeks of Pregnancy. She has a boy of 8 years old who has cerebral lesion. Now the doctors said to her that the baby inside her belly has a reciprocal translocation in the chromosomal 18 and 21. You think this baby will have any problem? Where She lives there is not any technology to help her more. Can you tell me please. We are devastated. And the doctors said that she need to have an abortion. Please help. Maybe this baby is healthy and they commit an error
Magda Luz What was the outcome?
I hope the baby is here happy and healthy!
Where did all of those eggs come from? Lol... but great video.
I think there are 4 different probabilities of producing one egg cell; he showed all possible outcomes!
1/232 value of down's syndrome ,so i got through amniocentesis.what do you think.my age is 35.my first two babies are normal.too upset n waiting for results.plz reply
It would be more helpful if you showed what normal looked like first. Also, too much repetition and use of terms I don't know lol
Are you from Massachusettes?
like and thank u
I have to like see this a hundred times and I still don't get it. At what point exactly do cells reproduce, when does disjunction take place, is is like happening all the time. Sorry, totally daft and ignorant
You need to buy a Mike please
👍👏
thanks,great sir
thanks,great sir
thanks,great sir
thanks,great sir