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13 Famous People with Klinefelter Syndrome or Marfan Syndrome

Famous people with Klinefelter Syndrome or Marfan Syndrome:


Klinefelter syndrome (47, XXY) is a condition that occurs in men who have an extra X chromosome, resulting in an XXY sex chromosome karyotype.

The syndrome can affect different stages of language, physical, and social development. It is estimated that 3,000 affected boys are born each year in the US.


The signs and symptoms of KS in young boys and teenagers may include:

  • a quiet character;
  • tall stature (short torso, long legs, and broader hips);
  • shyness;
  • small penis;
  • fatigue;
  • small, firm testicles;
  • weak bones;
  • gynecomastia (enlarged breast tissue).

Note – since KS can be hard to notice, many parents don’t know their child has the syndrome until he shows delays in puberty.

People who have KS have an increased risk for autoimmune disorders, like – rheumatoid arthritis, lupus, and Sjogren’s syndrome. Also, the syndrome is linked with an increased risk for breast cancer, varicose veins, lung disease, extragonadal germ cell tumor, and osteoporosis.


Testosterone therapy can help sufferers with many of the symptoms of KS, but the treatment should start at puberty.

Marfan Syndrome

Marfan Syndrome

Marfan syndrome wrist sign hypermobility long fingers

Marfan syndrome is an inherited disease that affects the body’s connective tissue, which provides support, strength, and elasticity to blood vessels, cartilage, heart valves, tendons, and other important parts of the physical body.

This autosomal dominant condition occurs once in every 10,000 to 20,000 people. It is named after Antoine Marfan, a French doctor who first described the syndrome in 1896.

If you have MS, you have a 50:50 chance of passing on the condition to each of your children.


Common symptoms may include:

  • backward flow of blood through the aortic and mitral valves;
  • floppiness of the mitral valve;
  • tear (dissection) and widening (aneurysm) of the main artery;
  • nearsightedness (myopia);
  • dislocation of the lenses of the eyes (ectopia lentis);
  • protrusion of the chest wall (pectus deformity);
  • an abnormal side-to-side curvature of the spine (scoliosis);
  • overgrowth of the long bones of the legs and arms.

Note – because of the high degree of variability of the syndrome, many of these clinical characteristics can be present at birth or they can manifest later in childhood.


It can be difficult to diagnose since many sufferers have only a few typical symptoms and no specific biochemical or histologic changes.

List Of Celebrities, Actors, And Other Famous People Who Have (or are rumored) Klinefelter Syndrome or Marfan Syndrome:

1) Austin Carlile

Austin Carlile

© Getty Images

He was born on September 27, 1987, in Ohio, and is best known as the former lead vocalist of the bands ”Attack Attack!” and ”Of Mice & Men.”

In 2005, Austin formed Call It Even with his high school friends. 

He was diagnosed with Marfans at age 17.

Austin is undergoing a long procedure to battle the effects of Marfan syndrome.

2) Brooke Moore

Originally named Bradley, she was assigned the male gender at birth and went to an all-boys school. Eventually, Moore was diagnosed with Klinefelter syndrome.

3) Peter Mayhew

Peter Mayhew

© Getty Images

Peter earned a place in cinematic history for his role as Chewbacca in the Star Wars franchise.

He was also diagnosed with Marfan syndrome.

4) Niccolo Paganini

Niccolo Paganini

© Getty Images

He was a renowned Italian violinist and composer of the 19th century who is best remembered for his ”24 Caprices for Solo Violin Op 1,” that he wrote between 1802 and 1817.

The American Schonfeld was the first to advance the theory that Niccolo Paganini was affected by the Marfan syndrome.

5) Troye Sivan

Troye Sivan

© Getty Images

He is a singer and actor of Australian origin, born in 1995. Troye Sivan started off as a singer in 2006 and in 2008 he released his first original music album.

Sivan is also quite popular on social media, including Instagram (where he has more than 7 million followers) and YouTube (where his audience includes over 6.2 million people).

Troye suffers from a mild form of Marfan syndrome.

6) Isaiah Austin

Isaiah Austin

© Getty Images

He is an American basketball player who played two years of college basketball for Baylor University. Moreover, Isaiah had been considered a first-round prospect in the 2014 NBA draft.

On June 22, 2014, Isaiah had been diagnosed with Marfan syndrome.

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7) Vincent Schiavelli

Vincent Schiavelli

© Getty Images

Vincent was an actor that had made over 120 television and film appearances.

He was also selected in 1997 by Vanity Fair as one of the best character actors in the United States.

Schiavelli was diagnosed with Marfan syndrome.

In addition, he worked at the national conference helping teens with MS, whom he called his “genetic brothers and sisters.”

He died of lung cancer at age 57 in Italy.

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8) Michael Phelps

Michael Phelps

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He was born to Deborah Sue ‘Debbie’ and Michael Fred Phelps in Baltimore, Maryland.

Phelps won 6 gold medals at the 2004 Olympics, 8 gold medals at the 2008 Olympics, and 4 gold medals at the 2012 Olympics.

He is the most celebrated athlete and the most decorated Olympian ever in the history of sports.

It was rumored that Michael Phelps, however, he tested negative for it. Phelps also wrote in his autobiography that he does not have MS.

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9) Peter the Great

Peter the Great

© Getty Images

Peter the Great was the Tsardom of Russia from May 1682 until his death in 1725.

It is thought that he had MS.

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10) Sergei Rachmaninoff

Sergei Rachmaninoff

© Getty Images

He was a composer and the last great figure of the Russian Romanticism tradition.

The size of his hands may have been a manifestation of MS.

However, he did not clearly exhibit any of the other clinical features typical of the syndrome.

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11) Arik Einstein

He was a vocalist for Shleeshiyat Gesher Hayarkon (Yarkon Bridge Trio), Batzal Yarok (Green Onion), and Hahalonot Hagvohim (The High Windows).

Arik had Marfan Syndrome. He died at the age of 74 at Ichilov Hospital in Tel Aviv, a few hours after he suffered a fatal hemorrhage.

#12) Andy Jackson

Andy Jackson is an Australian poet diagnosed with Marfan.

“When I was first diagnosed there was talk that the normal Marfan lifespan was 30 to 40 years,” Andy told ABC. He added: “Nowadays, if people are aware that they have it and they’re monitored and live appropriately, they can have quite a normal lifespan.”

#13) Heinrich Alexandra Hermann

klinefelter syndrome celebrities with turner syndrome


Heinrich Alexandra Hermann is an individual who was born with Klinefelter syndrome. In 2021, Schwenningen wanted to be the “only diverse direct candidate” in the election for the Left Party in the Bundestag. 

Featured image credit – Getty Images

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