Poland Syndrome

Poland Syndrome is a syndrome that - in some cases - may be considered an intersex variation, although many would say it causes intersex traits, rather than being one in of itself. This syndrome affects 1 in 20,000 newborns, however it is twice as common in CTM people than CTF people, for unknown reasons.

In both CTF and CTM individuals with this syndrome, secondary sex traits are heavily affected, and is one of the top symptoms of Poland Syndrome. Those with this syndrome often are born without nipples, without breasts, with small breasts, and/or small nipples. In CTM individuals with the syndrome, undescended testicles and hypospadias are also common.

Other symptoms include an chest abnormalities, absent fat, fused ribs, missing or short ribs, missing muscles, a high shoulder blade, an absent hand, extra fingers, abnormal fingerprints, webbed fingers, a split hand, webbed toes, vertebrae/back abnormalities, scoliosis, a high hairline, and/or diabetes.

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

Causes
The cause of Poland syndrome is unknown, however researchers have suggested that it may result from a disruption of blood flow during development before birth. This disruption is theorized to occur at about the sixth week of embryonic development and affect blood vessels that will become vertebral arteries on each side of the body, which are arteries that supply blood to embryonic tissues that give rise to the chest wall and hand on their respective sides, hence the abnormalities.

Despite this theory, there is no confirmation of the real cause.

History
This syndrome was named by Patrick Clarkson, a British plastic surgeon, in 1962. Clarkson was working at Guy's Hospital and Queen Mary's Hospital in London, when he noticed that three of his patients had both a hand deformity and an underdeveloped breast on the same side. He discussed this with his colleague at Guy's Hospital, Dr Philip Evans, who agreed that the syndrome was "not widely appreciated".

Clarkson decided to look into it, and upon doing so, found a reference to this same syndrome published by Alfred Poland in 1841 Guy's Hospital reports. This single case report wasn't enough for Poland to be able to identify it as a syndrome, however Clarkson's reports mixed with Polands certainly were, and this is what caused Clarkson to name this syndrome the 'Poland Syndrome' after the original person to discover it.

Resources

 * https://rarediseases.info.nih.gov/diseases/7412/poland-syndrome
 * https://medlineplus.gov/genetics/condition/poland-syndrome/#frequency
 * https://www.healthline.com/health/poland-syndrome#causes
 * https://en.wikipedia.org/wiki/Poland_syndrome