Down Syndrome: Cause, Progression, and Treatment

An error occurred trying to load this video.

Try refreshing the page, or contact customer support.

Coming up next: Guillain-Barre Syndrome: Sudden Paralysis

You're on a roll. Keep up the good work!

Take Quiz Watch Next Lesson
Your next lesson will play in 10 seconds
  • 0:07 The Very Front of Your Brain
  • 0:38 What Is Down Syndrome?
  • 1:16 Why Does Down Syndrome Occur?
  • 3:46 Clinical Signs,…
  • 5:00 Treatment of Down Syndrome
  • 5:24 Lesson Summary
Save Save Save

Want to watch this again later?

Log in or sign up to add this lesson to a Custom Course.

Log in or Sign up

Speed Speed

Recommended Lessons and Courses for You

Lesson Transcript
Instructor: Artem Cheprasov

Artem has a doctor of veterinary medicine degree.

This lesson will discuss a condition called Down syndrome. You'll learn why it occurs, how genetics may play a role, how the brain may be affected, and what other problems this disorder may cause. We'll also discuss how this condition may be diagnosed.

The Very Front of Your Brain

In life, everyone wants to be in front. We want to be at the front of the line, sit at the front of a window, or be at the forefront of medicine. That's because the word 'front' implies something superior or better or more desirable somehow.

Our brain is kind of similar. The very front of our brain has a region that is involved in some of the most superior tasks a human being can possibly accomplish. We'll explore how this area of the brain may be involved in a very serious condition.

What Is Down Syndrome?

This condition is called Down syndrome, and it is the most common chromosomal abnormality, one that leads to severe intellectual disabilities and health problems. One in about 700 to 1000 children will be born with this condition. Most children with this problem are born to mothers under the age of 35, but older mothers have an increased risk of having a child with Down syndrome. For example, the chances that a woman aged 45 will have a child with Down syndrome are 20 times greater than normal.

Why Does Down Syndrome Occur?

However, women aren't solely to blame here by any means. The reason this genetic condition occurs is as follows. When a baby is conceived, it receives 23 chromosomes from its mother and 23 chromosomes from its father for a total of 46 chromosomes. The way to remember that is to think about the fact that the perfect number of chromosomes you can get from either your mother or father is 23. That would be considered to be a slam dunk, exactly what you want. And who's the best NBA player in history? Michael Jordan, number 23 for the Chicago Bulls.

A chromosome is just a really compact string of DNA, the genetic information that makes you who you are. You can liken a chromosome to a wire you get with a new smartphone. The wire is just one long string-like thing, but it comes coiled in the box so it can fit in there. That's what chromosomes are; they are coiled in your cells so they can fit inside of it.

In any case, when an egg or sperm has an extra chromosome, the child will have 47 total chromosomes, leading to a child developing Down syndrome. The reason for why an extra chromosome appears in the egg or sperm is unknown. One thing we know for sure is that chromosome 21 is the chromosome whose additional copy in the egg or sperm causes a child to develop Down syndrome. That's why another name for Down syndrome is trisomy 21, since you have two, plus one extra, chromosome 21.

The way I remember which chromosome spoils the party, so to speak, is to think about your 21st birthday and how an uninvited guest just decides to show up and ruin everything in sight. That's the gist of what happens in Down syndrome as well. The addition of the extra chromosome leads to a whole host of problems way beyond what your trashed birthday party could ever cause you.

One thing that has been noted is that children with Down syndrome seem to have difficulties in tasks involving many areas of the brain, including the prefrontal cortex, an area of the brain responsible for behavior, attention, decision making, emotion, and complex thought. Since it's so important in so many areas of life, it's no surprise that the prefrontal cortex is at the very front of your brain just like someone of equal importance would want to be at the front of a line.

Clinical Signs, Symptoms, and Diagnostics

The effect the extra chromosome may have on the prefrontal cortex and other areas of the brain may explain some of the signs and symptoms associated with this condition, such as intellectual disabilities, late onset of motor activities (such as walking), and seizures. Unfortunately, the additional chromosome may cause a lot more than just neurological issues; these include heart disease, infertility, and vision and hearing disorders in addition to the stereotypical physical malformations associated with this condition, such as a short neck, small head, and flat face.

To unlock this lesson you must be a Member.
Create your account

Register to view this lesson

Are you a student or a teacher?

Unlock Your Education

See for yourself why 30 million people use

Become a member and start learning now.
Become a Member  Back
What teachers are saying about
Try it risk-free for 30 days

Earning College Credit

Did you know… We have over 200 college courses that prepare you to earn credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the first two years of college and save thousands off your degree. Anyone can earn credit-by-exam regardless of age or education level.

To learn more, visit our Earning Credit Page

Transferring credit to the school of your choice

Not sure what college you want to attend yet? has thousands of articles about every imaginable degree, area of study and career path that can help you find the school that's right for you.

Create an account to start this course today
Try it risk-free for 30 days!
Create an account