# Can animals have Down Syndrome?

**URL:** <https://boards.straightdope.com/t/can-animals-have-down-syndrome/175456>\
**Category:** Factual Questions\
**Created:** [May 15, 2003, 3:40pm UTC](https://boards.straightdope.com/t/can-animals-have-down-syndrome/175456 "2003-05-15T15:40:57Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![JKB](https://avatars.discourse-cdn.com/v4/letter/j/7feea3/32.png) [@JKB](https://boards.straightdope.com/u/JKB)\
**Post date:** [May 15, 2003, 3:40pm UTC](https://boards.straightdope.com/t/can-animals-have-down-syndrome/175456/1 "2003-05-15T15:40:57Z")

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Or to be more precise, can animals be born with a rouge “extra chromisone” that causes physical defects the same way a 23rd chromisone causes problems for humans?

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**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\
**Post date:** [May 15, 2003, 3:48pm UTC](https://boards.straightdope.com/t/can-animals-have-down-syndrome/175456/2 "2003-05-15T15:48:47Z")

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Yes.

[http://www.np.edu.sg/~dept-bio/rdna/geng/downsyndrome.htm](http://www.np.edu.sg/~dept-bio/rdna/geng/downsyndrome.htm)

> [@](#):
>
> **Mouse Models**
> 
> ```
> One of the first mice to be studied in relation to Down's Syndrome was the "trisomy 16" mouse. This was because a large portion of mouse chromosome sixteen is syntenic to a portion of human chromosome twenty-one. These mice live to adulthood but have learning and behavioral deficits. Another new and significant model is provided by an "in vivo library" of mice that are transgenic for a set of human YAC and P1 clones. A dosage-sensitive effect can be mapped to a critical region, and candidate genes can be analyzed. 
> 
> ```

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**Author:** ![Desmostylus](https://avatars.discourse-cdn.com/v4/letter/d/c57346/32.png) [@Desmostylus](https://boards.straightdope.com/u/Desmostylus)\
**Post date:** [May 15, 2003, 3:54pm UTC](https://boards.straightdope.com/t/can-animals-have-down-syndrome/175456/3 "2003-05-15T15:54:27Z")

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Yes.

[http://www.np.edu.sg/~dept-bio/rdna/geng/downsyndrome.htm](http://www.np.edu.sg/~dept-bio/rdna/geng/downsyndrome.htm)

> [@](#):
>
> **Mouse Models**
> 
> ```
> One of the first mice to be studied in relation to Down's Syndrome was the "trisomy 16" mouse. This was because a large portion of mouse chromosome sixteen is syntenic to a portion of human chromosome twenty-one. These mice live to adulthood but have learning and behavioral deficits. Another new and significant model is provided by an "in vivo library" of mice that are transgenic for a set of human YAC and P1 clones. A dosage-sensitive effect can be mapped to a critical region, and candidate genes can be analyzed. 
> 
> ```

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**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\
**Post date:** [May 15, 2003, 4:02pm UTC](https://boards.straightdope.com/t/can-animals-have-down-syndrome/175456/4 "2003-05-15T16:02:45Z")

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Of course, those syndromes are only similar to Downs Syndrome, and not exactly the same, because different species have different chromosomal arrangements. Most trisomies are invariably fatal. Only trisomies of small insignificant chromosomes are likely to be survivable.