Society has come a long way since circus “freak shows” put little people on display. But people with dwarfism are not very common, so they may still maintain a certain level of mystery for many of their average-sized neighbors. Here are a few facts to clear things up.

Some people are just short

Being short does not mean you have dwarfism, which comes from a medical or genetic condition. Dwarfism “usually results in an adult height of [4 feet 10 inches] or shorter, among both men and women,” according to Little People of America. But there are other medical causes of short stature, such as a low-functioning thyroid gland or malnutrition. Other people are just not tall, and don’t have any medical condition.

Read: Why You Are Short Or Tall

Some little people are not that little

Just like there are short people without dwarfism, there are people with dwarfism who are not that petite. Little People of America says the typical height range in dwarfism can be up to 4 feet 8 inches, although some are taller than 4 feet 10 inches.

Peter Dinklage knew this already. _

There are many different kinds of dwarfism

It’s not a one-size-fits-all label. Achondroplasia is the most common cause of dwarfism, and it largely occurs in people whose parents are average height, according to the Mayo Clinic. That condition causes disportionately sized arms and legs.

There is also Turner syndrome, which affects only females and is linked to genes that determine a person’s sex, among many other types.

Certain groups are more at risk

According to the U.S. Genetic and Rare Diseases Information Center, that most common form of dwarfism, achondroplasia, occurs more often in certain areas. In Denmark, it accounts for one in 6,400 births, while in Latin America that number is one in 10,000.

End of story. 30 Rock

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