Posted anonymously for a member: I plan on applying to med school soon (MD/PhD). I have a few summer research experiences. I have one lab research experience which lasted about 2 years. The research experience was initially not that bad but soon turned horrible. I started the research through a class, which I received an A in from the PI. Before the research class, I had known the PI for 2 years. I had taken and received As in a couple of classes taught by the PI before the research course. I looked up to the PI as a mentor and often went to them for advice over the two years. The PIs temper would explode every once in a while in the lab (which was a side of them I had not seen before) but I really wanted to do the research, so I tried not to let it get to me. My school started giving out competitive research mentorships. At the end of the research class, the PI suggested that I apply for one and keep working in their lab through it. I applied and was awarded one. Not too far into the mentorship, the PI became very verbally and emotionally abusive and made a lot of inappropriate comments towards me, yet I was determined to complete my mentorship. Towards the end of the semester, my physician advised me to take a leave of absence from school because of the immense stress I was under. I took a couple weeks off and went back to school, continuing the mentorship (I only had about 6-7 months left, and really wanted to complete the mentorship). For lack of a better phrase, when I went back to the lab after a few months all hell broke loose. My research PI often liked to yell at me for small things usually referencing stereotypes and using a lot of demoralizing and degrading comments. The straw that broke the camels back was when she started yelling at me because I didnt say much in the lab. I usually was quiet because I felt that me saying anything would only provoke her to explode. When she was done yelling, I apologized and left for the day. Looking back, the cycle was that she would always yell at me, and then the next day she would apologize to me and give me a hug. The last time she yelled at me, a few people must have overheard. Because, anonymous complaints were received by the mentorship director about how I was being treated. I never continued working in the lab after that. However, how am I going to explain not having a letter of recommendation from my lab research PI with whom I worked for 2 years??? I am concerned because I heard MD/PhD programs want letters from all of your research PIs.