Brachydactyly type D

High school (ages 12+)
Human Body

Name:

Date:

Step 1 · Read the article

Open the article and read it at the level above. Then answer the questions below in your own words.

https://smallwhale.org/articles/brachydactyly-type-d

Write what each word means, using the article.

Do not copy the article. Write two things you learned, the way you would explain them to a friend.

Answers below are taken from the article’s stored facts, so they match what the student read.

1. What is the genetic locus?Associated with the HOXD13 gene located on chromosome 2q31.1
2. What is the inheritance pattern?Typically inherited in an autosomal dominant manner
3. Why does the thumb look shorter in Brachydactyly type D?Because the last bone of the thumb is about two‑thirds the usual length, making it look more rounded.
4. Does Brachydactyly type D affect how well someone can use their thumb?Usually it doesn't hurt grip or dexterity; people can use their thumbs normally.

Distal Phalanx: The terminal bone segment of a finger or toe, located furthest from the hand or foot.
HOXD13 Gene: A homeobox gene critical for embryonic limb development, variations of which are linked to Brachydactyly type D.
Autosomal Dominant Inheritance: A pattern of inheritance where a single copy of a mutated gene from one parent is sufficient to cause the trait.
Phenotypic Variation: Differences in observable physical or biochemical characteristics among individuals.