Robin Roberts, the popular co-host of ABC’s "Good Morning America," announced this morning that she will begin treatment for myelodysplastic syndromes or MDS. Unlike cancer or HIV, this disease hasn’t spent much time in the spotlight, and few know much about it.

MDS is actually a group of diseases that affect the blood and bone marrow — the spongy material inside of bones where blood cells are created. “Myelo” refers to blood cells and “dysplastic” refers to abnormal development or growth — thus, myelodysplastic syndrome indicates that blood cells have an unusual shape and that they have abnormal growth, according to The Aplastic Anemia and MDS International Foundation.

Myelodysplastic syndromes happen when something disrupts the regular production of blood cells. According to the Mayo Clinic, people with myelodysplastic syndromes have blood cells that are immature and defective, and instead of developing normally, they die in the bone marrow or just after entering the bloodstream. Over time, the number of immature, defective cells begins to surpass that of healthy blood cells, leading to problems such as anemia, infections and excess bleeding.

Some forms of MDS are mild, other types are severe and life-threatening — and mild cases of MDS can become worse over time. They can also develop into the severe, quick-spreading leukemia known as acute myelogenous leukemia.

About 10,000 to 15,000 people are diagnosed with MDS in the United States each year.

Myelodysplastic syndromes are divided into two categories based on their cause:
 

Myelodysplastic syndromes with no understandable cause are known as de novo myelodysplastic syndromes, and nobody knows what causes these. This category is often easier to treat than are myelodysplastic syndromes with a known cause.
 

Myelodysplastic syndromes caused by chemicals and radiation are the second category — these can be the result of cancer treatments (chemotherapy and radiation) as well as a response to chemical exposure. These are called secondary myelodysplastic syndromes and they are often more difficult to treat. Roberts is a breast cancer survivor who underwent chemotherapy.

The World Health Organization further divides myelodysplastic syndromes into subtypes based on the type of blood cells (red cells, white cells and platelets) that are involved. 

Symptoms may include, according to the Mayo Clinic:

  • Fatigue
  • Shortness of breath
  • Unusual paleness (pallor) due to anemia
  • Easy or unusual bruising or bleeding
  • Pinpoint-sized red spots just beneath your skin caused by bleeding (petechiae)
  • Frequent infections
There is no cure for myelodysplastic syndromes, but there are treatments that focus on reducing or preventing complications of the disease. Treatments include chemotherapy, medications, blood transfusions and bone marrow stem cell transplants, which is the treatment that Roberts will receive.

As Roberts noted, “Bone marrow donors are scarce and particularly for African-American women. I am very fortunate to have a sister who is an excellent match, and this greatly improves my chances for a cure. As you know from my recent interview with Mark Zuckerberg, organ donation is vitally important. Many people don't realize they can be bone marrow donors. I encourage everyone to sign up on a donor registry like bethematch.org.”

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