Does Alphys have a gender?

Ok, I've always known a bit about Undertale and Delta Rune because of friends and family who enjoyed it. I finally decided to play it and stop relying on random videos I saw. need to know, does Alphys have a gender? I know, I know that there was a post about this already saying Alphys is a girl, but while I was hanging out with Undyne when I went to the piano, she talked about Alphys being a little weird and said something along the lines of "he always creeped me out." Is this a mistake? I always got feminine vibes from Alphys and I'm pretty sure the wiki said Alphys is a she, but ??? Any thoughts? What ending did you do your first run?