DE LA CHAPELLE

What is it?
It is a syndrome caused by unequal crossing over between X and Y chromosome during meiosis in the father, where the X chrom. gets the SRY gene.

SRY

Once this X combines with an X from the mother, this results in an XX male.

This syndrome makes a person phenotypically male but genetically female.

Albert De La Chapelle

EFFECTS OF

EFFECTS

• Small Testicles
• Breasts
• Female Pubic Hair Pattern
• Poor Beard Growth
• Tall stature
• No libido
• Sterile

Frequency!
Approximately 1 in 20,000 individuals with a male appearance have XX male syndrome.

Is it Hereditary?

• Rarely gets passed down
• Affected people can't pass it down because they are infertile
• However, there still are carriers.

SRY Positive

• Main form of it
• 80 percent of people with this syndrome have this form

SRY Negative

• Rare form of it
• 20 percent of people with this syndrome have this form