Aarskog-Scott Syndrome

Aarskog-Scott Syndrome is a condition that - in some cases - may be considered an intersex condition, although many would say it causes intersex conditions rather than being one in of itself. This condition effects both CTM and CTF individuals, however it is more likely to effect CTM people. Its rarity is unknown, as mild cases are theorized to go undiagnosed and without notice.

This condition can cause cryptorchidism, a misplaced clitoris (such as a clitoris that is below the vagina), and/or a shawl scrotum, putting many with this syndrome on the intersex spectrum.

80-99% of those with this condition have broad feet, short feet, broad palms, small hands, camptodactyly within a finger, umbilical hernia, short stature, widely spaced eyes, and a drooping lower lip.

30-79% of those with this condition have a broad forehead, low set/rotated ears, external ear malformation, a wide nasal bridge, an upturned nasal tip, a long philtrum, a drooping upper eyelid, downslanting eyelids, cognitive impairment, and/or hyperelastic skin.

5-29% of those with this condition have abnormal vertebral segmentation and fusion, ADHD, a cleft palate, a cleft lip, epicanthus, cross eyes, an enlarged cornea, delayed teeth growth, jaw abnormalities, a round face, a short neck, a funnel chest, cardiac failure, a back knee, and/or flat feet.

Those with this condition may or may not experience a delayed puberty, or symptoms that are similar but not quite the same as the ones listed above.

It is important to note that not all the symptoms listed above are guaranteed to occur in someone with this condition, as someone may only experience one or several of these symptoms, yet still hold the condition.

Causes
Mutations in the FGD1 gene are the only known genetic cause of Aarskog-Scott syndrome. The FGD1 gene provides instructions for making a protein that turns on (activates) another protein called Cdc42, which transmits signals that are important for various aspects of development before and after birth. This abnormality caues a change of genetic development, starting from in the fetal state.

Only 20% have this mutation as the cause of their condition. It is unknown what causes this condition in people who do not FGD1 gene mutations.

Resources

 * https://rarediseases.info.nih.gov/diseases/4775/aarskog-syndrome
 * https://medlineplus.gov/genetics/condition/aarskog-scott-syndrome/
 * http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1677-55382006000400014