This looks like an issue that someone else reported with regards to exporting models created in MakeHuman.
If I’m not much mistaken, the issue in that case was that the materials had transparency assigned: in a “Properties” panel, go to the “Material” tab. For each material, scroll down to “Transparency” and make sure that the value of “Alpha” is 1 and that “Transparency” is disabled. (I’m honestly not sure that the “Transparency” check is used; the important thing is that the “Alpha” value is 1, regardless of the state of the “Transparency” check-box, I believe.)