What is Down syndrome?
Down syndrome is a developmental disorder caused by an extra copy of chromosome 21. This disorder is caused by an error in cell division that results in an extra 21st chromosome. Having an extra copy of this chromosome means that each gene may be producing more protein product than normal. Cells seem to tolerate this better than having not enough protein, or having altered protein due to a mutation in the DNA sequence.
The condition leads to impairments in both cognitive ability and physical growth that range from mild to moderate developmental disabilities. Through a series of screenings and tests, Down syndrome can be detected before and after a baby is born.
The only factor known to affect the probability of having a baby with Down syndrome is maternal age. That is, less than one in 1,000 pregnancies for mothers less than 30 years of age results in a baby with Down syndrome. For mothers who are 44 years of age, about 1 in 35 pregnancies results in a baby with Down syndrome. Because younger women generally have more children, about 75 – 80% of children with Down syndrome are born to younger women.
How do people get Down syndrome?
Down syndrome occurs because of an abnormality characterized by an extra copy of genetic material on all or part of the 21st chromosome. Every cell in the body contains genes that are grouped along chromosomes in the cell’s nucleus or center. There are normally 46 chromosomes in each cell, 23 inherited from your mother and 23 from your father. When some or all of a person’s cells have an extra full or partial copy of chromosome 21, the result is Down syndrome.
Down syndrome is typically caused by what is called nondisjunction. If a pair of number 21 chromosomes fails to separate during the formation of an egg (or sperm), this is referred to as nondisjunction. When that egg unites with a normal sperm to form an embryo, that embryo ends up with three copies of chromosome 21 instead of the normal two. The extra chromosome is then copied in every cell of the baby’s body. Nondisjunction events seem to occur more frequently in older women. This may explain why the risk of having a baby with Down syndrome is greater among mothers age 35 and older.
What are the symptoms of Down syndrome?
Despite the variability in Down syndrome, individuals with Down syndrome have a widely recognized characteristic appearance. Typical facial features include a flattened nose, small mouth, protruding tongue, small ears, and upward slanting eyes. The inner corner of the eyes may have a rounded fold of skin (epicanthal fold). The hands are short and broad with short fingers, and may have a single palmar crease. White spots on the colored part of the eye called Brushfield spots may be present. Babies with Down syndrome often have decreased muscle tone at birth. Normal growth and development is usually delayed and often individuals with Down syndrome don’t reach the average height or developmental milestones of unaffected individual.
How do doctors diagnose Down syndrome?
Three types of tests check for Down syndrome during a woman’s pregnancy: screening and diagnostic tests.
Screening tests identify a mother who is likely carrying a baby with Down syndrome. The most common screening tests are the Triple Screen and the Alpha-Fetoprotein Plus. These tests measure levels of certain substances in the blood.
Alternatively, ultrasounds (which use sound waves to look inside the mother’s uterus) allow the doctor to examine the fetus in the womb for the physical signs of Down syndrome.
To confirm a positive result identified in a screening test, one of the following diagnostic tests can be performed: chorionic villus sampling (CVS), amniocentesis. Each takes a sample from the placenta, amniotic fluid, or umbilical cord, respectively, to examine the baby’s chromosomes and determine if he or she has an extra chromosome 21.
If Down syndrome is not diagnosed in the womb, doctors can usually recognize it after the baby is born by the distinctive facial features. The diagnosis is confirmed with a karyotype – an examination of the baby’s chromosomes.
Amniocentesis, chorionic villus and ultrasound are the three primary procedures for diagnostic testing, which can identify certain abnormalities in the fetus.
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Amniocentesis
— Amniocentesis is used most commonly to identify chromosomal problems, such as Down syndrome. When the fetus is known to be at risk, it can detect other genetic diseases like cystic fibrosis, Tay-Sachs disease and sickle cell disease. An amniocentesis procedure for genetic testing is typically performed between 15 and 20 weeks of pregnancy. Under ultrasound guidance, a needle is inserted through the abdomen to remove a small amount of amniotic fluid. The cells from the fluid are then cultured and a karyotype analysis — an analysis of the chromosomal make-up of the cells — is performed. It takes about two weeks to receive the results of the test.Amniocentesis detects most chromosomal disorders, such as Down syndrome, with a high degree of accuracy. Testing for other genetic diseases, such as Tay-Sachs disease, is not routinely performed but can be detected through specialized testing if your fetus is known to be at risk. Testing for neural tube defects, such as spina bifida, also can be performed. There is a small risk of miscarriage as a result of amniocentesis — about 1 in 100 or less. Miscarriage rates for procedures performed at UCSF Medical Center are less than 1 in 350.
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Chorionic Villus Sampling (CVS)
– Like amniocentesis, chorionic villus sampling is used most commonly to identify chromosomal problems, such as Down syndrome. It can detect other genetic diseases like cystic fibrosis, Tay-Sachs disease and sickle cell disease in at-risk fetuses. The main advantage of CVS over amniocentesis is that it is done much earlier in pregnancy, at 10 to 12 weeks, rather than 15 to 20 weeks.CVS involve removing a tiny piece of tissue from the placenta. Under ultrasound guidance, the tissue is obtained either with a needle through the abdomen or a catheter inserted through the cervix. The tissue is then cultured and a karyotype analysis &mash; analysis of the chromosomal make-up of the cells — is performed. It takes about two weeks to receive the results.
The advantage of CVS over amniocentesis is that the test is performed much earlier in pregnancy, so results are typically available by the end of the third month. A disadvantage is that spinal cord defects cannot be detected. Expanded alpha fetoprotein (AFP)blood testing or ultrasound can be performed later in the pregnancy to screen for spinal cord defects.
There is a small risk of miscarriage as a result of CVS — 1 in 100 or less. Miscarriage rates for procedures performed at UCSF Medical Center are less than 1 in 350.
Ultrasound
– The primary purpose of ultrasound is to determine the status of a pregnancy — the due date, size of the fetus and multiple gestations. Ultrasound also can provide some information about possible birth defects in a fetus. All patients at UCSF Medical Center undergo a comprehensive ultrasound examination before any invasive tests are performed. Results of the ultrasound are explained at the time of the visit.
In some patients, an ultrasound raises concern of a possible abnormality in the fetus. We have extensive experience in performing and interpreting ultrasounds in pregnancy.
How is Down syndrome treated?
No cure exists for Down syndrome. But physical therapy and/or speech therapy can help people with the disorder develop more normally. Screening for common medical problems associated with the disorder, followed by corrective surgery, can often improve quality of life. Moreover, enriched environments significantly increase their capacity to learn and lead a meaningful life.
Interesting facts about Down syndrome
- Down syndrome is really the only trisomy compatible with life. Only two other trisomies have been observed in babies born alive (trisomies 13 and 18), but babies born with these trisomies have only a 5% chance of surviving longer than one year.
- In 90% of Trisomy 21 cases, the additional chromosome comes from the mother’s egg rather than the father’s sperm.
- Down syndrome is the most common genetic disorder caused by a chromosomal abnormality. It affects 1 out of every 800 to 1,000 babies.
- Down syndrome was originally described in 1866 by John Langdon Down. It wasn’t until 1959 that a French doctor, named Jerome Lejeune, discovered it was caused by the inheritance of an extra chromosome 21.
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I hate the transition to a toddler bed, my hubby changed my oldest’s baby into the toddler bed way too soon! No more cage, so you wind up having to grow WITH the child and re-adapt to THEIR newly found and exhausting freedom,right?! Well, congrats on her graduation. I’m looking forward to getting to know you and your family as well. Thanks for the nice message. 
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Hello One and All…
I just want to share the good news that my family and I have been blessed with a beautiful blue-eyed blonde girl who is now eleven and was born with down syndrome. Her name is Elisabeth Anne, and she has been the joy of our lives! She is a delight to be around every day. She is very low maintenance and most of the time we don’t even know she’s around. She is never demanding of our time or of anything else for that matter. She is very eager to communicate and to learn. She goes to a nearby school for the deaf and the blind. We are very happy with her school for the most part. Her favorite things are… watching Barney and eating spaghetti. She loves going to church also. She likes to stay home. She’s definitely not a shopper like her mother. She has two brothers in their twenties who adore her. She is loved by all. She was also born healthy, so we’ve been blessed beyond measure. I did have to have her heart monitered for the first six months of her life since she was born with a hole in her heart. She’s also had several sets of tubes put in her ears. She is one happy gal who has taught us alot about love and getting along.
hi everyone i would just like to say that one of my best mates has DS and she is lovely and we have been mates for 5 yrs i thank people with DS are wonderful i think they are very gifted people.
Hello,
I have only today included an amazing little guy to my home day care setting. He is 14 months old. I knew I would want a safe and happy space for special needs to gather, as well as those without special needs. It is my passion to take my STNA
I am an aunt of a 7 yr old girl with down syndrome and I am really looking for forward to learning allot about children with down syndrome. I do have a question, I hope someone can answer me. There was a peom on here last week it was beautiful and I cant locate it. Does anyone know where I can find it? thank you
I am the father of a Down Syndrome teenager (13 yrs old). I found a way to educate people about Down Syndrome through a fictional thriller I wrote and published. I think people would enjoy the book and not realize they are learning about Down Syndrome. Check out my website LaffeyDownsBook.com
How is your book going? Let me know, maybe I can give it some placement on the site.
Justin
hey all i jus wanted to say the love of my life is my son who 7 months old this month an he has downsyndrome he is the greatest thing god could have given me at first i asked my sellf y this happened to me but now i no he was sent to me an i love him with every beat of my heart an wouldnt never change that hes the best thing to happen to me an my family we love him very much
This give us a lot to think about. Your experiences help many families so please don’t ever be hesitant to share. That is what this site is for. As we continue to make progress, we will certainly let you know…In fact, would you consider creating and moderating a “potty training” group on this site. I have been thinking about it for a while but could really use some help from someone that the topic is very important to…
just a thought.
This is just true warmth I fee that parents that don’t share our experiences could never feel. Thanks for sharing.
Justin
i have a beatiful girl baby six months old.
She is very calm-she initilly had swallowing problem, we treated her and she now improved. She can move herself upside down.
makes sounds.
congratulations! I would love to hear more about her…maybe you would like to create a blog or post some photos on you album? the group is getting to be really cool and friendly…feel free to add friends from the members tab.
Justin
Hi everyone, my name is joan and i have gorgeous 5 month old baby with down syndrome his name is Maximus. During my pregnancy I didn’t know anything so it was a big surprice but a beautiful surprice he is just the light of the when he smile i go crazy he makes my day.Thank u lord for my son thank u
I love that name…wonderful. thanks for finding the site and congratulations. I look forward to getting to know you better.
justin
hi everyone, i had a 5 months old baby who is affected with DS and now is no more he expired due cardio problem can you pls explain why this cardio prob arise after 5 months. he is not affected during his birth time. do this prob will arise at any time in his life time. kindly explain me
Manju,
It would probably be better to engage with members of the community by signing…Comments are a tough place to have this kind of discussion.
Justin
Hi,
I was blessed with the gift of two (2) Down Syndrome children born 4 years apart. Lauren is 8, will be 9 in January and Logan will be 5 in November. They are wonderful children, but every child has his/her moments. It takes a special individual/couple to parent children with DS. They require so much love, attention and patience, you have to be tireless in advocating for them in every setting. I am finding that I have a loud voice when it comes to standing up for my children. It is hard, but rewarding work. i just want to say to all parents that have or will have DS children: It’s a beautiful experience and you will grow so much as an individual by traveling on the less traveled path with your lovely children. I am now a single parent, and the road is hard at times, but those 2 little faces looking up at me every morning makes it all worthwhile.
Keep up this site, I loved reading all the comments.
Tamara
Tamara,
Thank you for you comments…They are inspiring and meaningful. We wish you the best on your journey.
Sincerely,
Justin
My parents are beginning the process of adopting a Down Syndrome boy from Mexico. His name is Julian and he’s three years old. My dad was reluctant at first to go through with the adoption. A few days ago, we found out that Julian was in the hospital because of pneumonia. Along with that, the CPS in Mexico wants to take him away from the orphanage he’s at right now. After my dad found out about this, he changed his attitude and agreed with my mom to go through with the adoption!
Pray that the adoption process will go smoothly and no problems. Also, Julian is doing much better but is still in the hospital.
Jessica
Hi my name is betty Iwas blessed with 2beautiful DS babies my oldest is 6 years old he was born on the 4th of july my youngest is going to be 4 months old they are the bestes gift that GOD has given me both of them are special in their own little way but you know what, i could of had 3 special DS kids but in the year of 2007 i lost a little girl with downs also.With me the story is that if i was to have another baby he/she would also be a downs also because i carry the extra chromosone in my egg sack and its always going to be a 99% that if i get pregnant my baby would be a DS baby so for right now i thank God for my 2 beautiful angels they always make every single day the best ever just to see their cute little faces every morning makes me a stronger mom to help them thru the path of life, i also have the bestest husband ever that helps me out, he is always holding on to our hands to never let go and always be there for us. Its nice to read all this beautiful stories keep it up
Thank you so much for sharing Betty. It sounds like you and your husband have your hands full but it also sounds like you have two great kiddos that will add wonderful texture to your life in the future. They are lucky to have parents as wonderful as you sound. Thanks for dropping by. I hope to get to know you and your family better over time.
Justin
My Wife is 30 weeks pregnant.We decided to have her tested for heredity Down Syndrome,her test shows her to be positive.she does not suffer or have any effects related to Down Syndrome.
What are the chances of our baby being born with down syndrome?
Thanks & Regards,
Gavin.
Encouraging all to give a “Thumbs UP to UP Syndrome.”
Hugs
http://www.facebook.com/pages/David-Pearce-Down-Syndrome-Brother-of-Kevin-Pearce-1000000-Fan-Club/320349778530?v=wall&ref=mf
Hi, my names alexa. I am doing a project on down syndrome and i would like to know if anyone can give me any information about a child or a person they know having downsyndrome. It would be greatly appretiated.
you can email me at: bapper27@aim.com
or my friends email:lexmill2009@yahoo.com
Thanks!
One general question:
Since testing can identify down syndrome why there are so many babies born with it? Maybe it is a stupid question but I just don’t get it.
Hi…This is a good question. Testing can identify if a child has trisomy 21 but it doesn’t change anything. Many people decide to get testing just so they can know and maybe make a difficult decision, others like my wife and me also had testing but it didn’t change anything for us…Just helped us prepare mentally.
Others only find out when the child is born. Irrespective, I think we all know that people with down syndrome have a special place in our hearts and society so it is really something that better testing won’t do anything about until science provides more thoughts and options.
justin
Hi,
My name is Shelli and my niece who is 5 months pregnant tested positive for a DS baby. We went to a specialist who wanted to do an amniocentesis but my niece chose not to do the procedure due to the risk of death. We are desperately looking for some resources and classes to help educate us about DS. My niece doesn’t care if the baby has DS as we will love her no matter what. We need to be educated and help us know what to expect. Anyone who has any info please help.
My cousin has down syndrome and even though she learns slower than others, she still brings light to her family including. I don’t know what we would do if she was any different.
Alex,
I agree. My son Teddy is the light of our lives and brings immense amounts of joy to my family. We would not change one thing about him. Thanks for making this great comment.
justin
I have twins. they will be four years old this saturday. MY son is healthy and My daughter has Down Syndrome. I am raising my twins on my own. My husband decided not to be part of their lives and we separated. I have been through some very difficult situations but I can honestly say that I feel very much loved by my babies, I feel I have matured and I feel like a better person because having a special child has made me view life from a different perspective. I enjoy the simple stuff and find every minute of laughter is worth more than anything around me. I want to congratulate all the parents that are raising special children because it is hard but it is a journey full of hope, love and overall life changing. It is not easy but it is very very rewarding. God Bless
Thank you so much for visition Paola! I want to congratulate you for everything you do.
Justin
hi i’m a mother who has downsyndrom son.he is 3th years old. His name Rahmandito Del Putra. I never take him go theraphy but he just fine. Now he can walk, he understand everything what I say. Many people like him.its make me happy and i dont upset about him. Bye
Wow, really enjoying this blog at the moment, I did a search and found it, so glad! I have just started with Yoga, and I enjoy what I’m reading here! How close is pilates to yoga though, just wondering?