How many chromosomes are in down syndrome?

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What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Down syndrome remains the most prevalent chromosomal disorder, with approximately 6,000 babies born with this condition each year. This equates to approximately 1 in every 700 babies born. In this article, we will understand about chromosomes, and discuss about the number of chromosomes present in down syndrome and whether having an extra chromosome is normal.

What is a chromosome?

A chromosome is a thread-like structure that consists of proteins and DNA. The DNA (deoxyribonucleic acid) contains the genetic material of an organisms and are responsible for passing on genetic information from one generation to the next. They are present in the nucleus of cells.

How many chromosomes are present in down syndrome?

In most cases of down syndrome, a person has an extra chromosome 21, equating to a total of 47 chromosomes instead of the usual 46. Sometimes, only part of chromosome 21 attaches to another chromosome. This extra genetic material causes the physical features and developmental delays seen in down syndrome.

Is having an extra chromosome normal?

No. Typically, individuals have 23 pairs of chromosomes, totalling 46 chromosomes. However, in down syndrome, an extra copy of Chromosome 21 is present. This condition is medically called ‘trisomy’. Hence, down syndrome is also known as Trisomy 21. The additional chromosome alters the development of the body and brain, leading to both physical and mental challenges for individuals with down syndrome.

Varying genetic material characterise different types of down syndrome. In Trisomy 21, each cell in the body has three copies of chromosome 21 instead of the typical two. Mosaic down syndrome occurs when only some of the body’s cells have an extra chromosome 21, whereas in translocation down syndrome, a portion of chromosome 21 becomes attached (translocated) to another chromosome either before or at the time of conception. These individuals possess two copies of chromosome 21 along with extra material from chromosome 21 attached to another chromosome.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

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What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

More in

Questions
Fact Check
Interviews
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Videos
What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

What is the number of chromosomes present in a person with down syndrome?
Down syndrome is distinguished by an additional chromosome 21 resulting in 47 chromosomes rather than the usual 46. Trisomy 21 has three copies of chromosome 21 in all cells, whereas mosaic down's syndrome has these copies in fewer cells. Translocation happens when one part of chromosome 21 attaches to another chromosome. Down syndrome results in physical feature variance and developmental delays.

Disclaimer: Medical Science is an ever evolving field. We strive to keep this page updated. In case you notice any discrepancy in the content, please inform us at [email protected]. You can futher read our Correction Policy here. Never disregard professional medical advice or delay seeking medical treatment because of something you have read on or accessed through this website or it's social media channels. Read our Full Disclaimer Here for further information.

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Dr. Shikha Shiromani
Dr. Shikha Shiromani
A dental surgeon by education and medical writer by profession, Shikha is passionate to bring her knowledge and experience in busting the myths around medicine and health. At THIP, she is involved in researching, fact-checking and answering all kinds of questions related to health.
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