https://www.jwatch.org/fw117364/2020/12/22/sars-cov-2-variant-not-yet-detected-us

One of the variant's mutations is the N501Y mutation in the receptor binding domain. Studies of other variants with N501Y have found that they may form a tighter bond to the human angiotensin-converting enzyme (ACE2) receptor. It is unknown whether this would translate into clinical or epidemiological differences. South Africa has also reported a SARS-CoV-2 strain with the N501Y mutation, but theirs appears to have emerged independently from the one in the U.K.