I didn't look at the link (didn't want to see more disturbing pics) but I have heard about this condition happening in humans. What is the prognosis for a baby born with HPE? Is the cause of HPE known? Is there a way to prevent it? Thanks.
The prognosis depends on the degree severity of the defect. It's essentially a lack of the midline of the brain, and sometimes the face. Severity depends on just how much of the midline is missing. There's a wide spectrum, and some children have only minor facial abnormailities, and behavioral problems. The very severe defects, like what this kitten had, are incompatible with life.
HPE is associated with maternal alcohol abuse during pregnance, maternal diabetes, and some other conditions that I can't remember off the top of my head. And it can of course occur without any precipitating factors. The very severe defects are, of course, very rare.