Hi @statmatics The causes of Blood cancers and conditions can be difficult to pinpoint. Many are caused by random mutations to a strand of DNA that starts the ball of destruction rolling. There can be genetic factors, behavioral influences known to be carcinogenic such as smoking, diet, environmental/chemical exposures, etc.. Most often, the cause of MDS is unknown. And really, it’s a moot issue…there is only going forward from this point.
I went through similar when I developed AML. My doctors weren’t trying to be evasive in my diagnosis. They (and I) simply will never know the precipitating factor that caused the radical changes to my DNA.

Myelodysplastic syndromes (MDS) are a group of conditions that interfere with your body’s ability to make healthy blood cells. In your case it appears to be red blood cells with the very low hemoglobin counts you’re experiencing.

You’ve most likely read articles and have gotten information from your hematologist/oncologist but I’ll toss a few resources in for a little reading material.
https://www.mayoclinic.org/diseases-conditions/myelodysplastic-syndrome/symptoms-causes/syc-20366977
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https://www.healthline.com/health/myelodysplastic-syndrome
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https://www.cancer.org/cancer/types/myelodysplastic-syndrome/causes-risks-prevention/risk-factors.html
There are different forms of MDS and knowing the specific subtype will dictate the type of treatments. Are you currently on any medications to help control the symptoms of your disease? What happens when your hemoglobin drops so significantly; Do you receive transfusions? Have there been indications of blast cells in your bloodwork?