Achondrogenesis, Noonan syndrome and sialadenitis aren’t household names. They have something else in common: Each is a rare disease. The term applies to any disease, disorder, illness or condition that affects fewer than 200,000 people in the United States.

More people have a rare disease than you might think. According to the National Institutes of Health, up to 30 million people in the United States — nearly 1 in 10 — live with rare diseases, and there could be as many as 7,000 of the conditions.

Rare diseases present real challenges to patients and medical professionals. One reason is a lack of data: An absence of surveillance for most of the conditions means statistical information can be scant.

So can treatments, which are often held up by a lack of research interest and a dearth of dollars. Since there’s relatively little demand from patients, drugmakers can abandon or never pursue therapies. More than 90 percent of rare diseases lack a Food and Drug Administration approved treatment.

“Our knowledge of most rare diseases is so insufficient that they are also known as orphan diseases because of their failure to attract the interest of researchers, medical specialists, drug makers, and policy makers,” researchers at the Centers for Disease Control and Prevention write.

But there’s hope for people with rare conditions, and a quick browse of the National Organization for Rare Disorders’ Rare Disease Database proves it.

The database contains reports on more than 1,200 of the disorders, from Aarskog syndrome, a rare genetic condition that produces facial, skeletal and genital abnormalities, to Zollinger-Ellison syndrome, which causes tumors that stimulate the production of stomach acid. It covers just about everything, such as symptoms, affected populations, diagnoses and known therapies.

Most important, the database identifies clinical trials and member organizations where patients can find more information and support.

NORD also offers educational videos, advocacy information and a patient registry.

With rare conditions, there is strength in numbers — and more information out there than you might think.

Curious about rare diseases? Visit the NORD at rarediseases.org to explore the database.