Magic genes

"Squibs are rare; magic is a dominant and resilient gene."

— Description of the nature of the magic gene

These genes were portions of human DNA that determined whether or not an individual had magical abilities. Those people born with the genes active were witches and wizards, while those who were born with the gene but it was inactive were Squibs, and those who did not have the gene at all were Muggles.

Description

Magic genes were described as being "dominant and resilient". Squibs, while unable to use magic, were often still able to function within the wizarding world to a limited degree. The descendants of squibs who instead integrated into the Muggle world and married would usually be Muggles, although the magical abilities occasionally resurfaced in later generations, producing a Muggle-born witch or wizard.

Behind the scenes

• According to J. K. Rowling, nobody knows where magic comes from.
• Since Lord Voldemort's ability to use magic survived even after his physical body had been destroyed, it can be assumed that magical ability has a connection to the soul. Further evidence would be Harry Potter's ability to speak Parseltongue while being a horcrux.
• J. K. Rowling stated that she had considered having Dudley Dursley have a magical child in the epilogue, and see them off to Hogwarts at Platform 9¾ at the same time as Harry and his family. She decided against this, however, stating that any latent wizarding genes would never survive contact with Uncle Vernon's DNA.
  • The Dursleys are most likely homozygous Muggles for the reasons mentioned above. Although if this is true, the impossibility of having a magical descendant would be determined by both Vernon and Petunia instead of solely because of Vernon.

Appearances

• Harry Potter and the Half-Blood Prince (Indirectly mentioned only)
• J. K. Rowling's official site (First mentioned)

See also

• Pure-blood
• Half-blood
• Muggle-born
• Squib
• Muggle

External links

• Paper sent to JK Rowling explaining how the wizarding gene could be singular, autosomal, and dominant (archived)