Environmental factors also play a strong role in modifying the conditions of the organism. One major problem in dealing with human specimens is that they do not come from controlled environments."[17] Additionally, there is little information regarding the samples of brains that Einstein's brain was compared against such as IQ score, or other relevant factors. Diamond also admitted that research disproving the study was omitted.[citation needed] His brain is now at the Mütter Museum in Philadelphia and two of the 140 sections are on loan at the British Museum.[18]