human
extract all the relation from the text: According to the results of the NGS assay, a total of 15 ESR1 variations in 13 patients were identified, including 13 ESR1 point mutations (substitutions or in-deletions) and 2 ESR1 amplifications. Among the 297 PBC patients, 5 ESR1 variant patients including 3 ESR1 point mutant patients and 2 CNV patients were identified, resulting in a 1% (3/297) ESR1 mutation rate among the PBC patients. 8 ESR1 mutation patients were identified among the 43 MBC patients, resulting in an 18.6% (8/43) ESR1 mutation rate in the MBC patients.
The 3 ESR1 mutations in the PBC patients comprised 3 mutation types: R555C, P535S, and A571 synonymous. The 10 ESR1 mutations in the 8 MBC patients comprised 6 mutations type: D538G (3/10), V422 in-frame deletion (1/10), E380Q (2/10), Y537N (1/10), Y537S (2/10), and L536H (1/10). All 13 ESR1 mutations were located within ER LBD, and 6 were hotspot mutations. The ESR1 mutations D538G, E380Q, and Y537S were recurrent mutations, which were all in the MBC patients. In addition, 2 MBC patients exhibited more than one ESR1 mutation (D538G plus V422 del, E380Q plus Y537N). Finally, for 3 ESR1-mutant MBC patients who could be matched to their pretreatment breast tumor tissues, no ESR1 mutation was detected in the earlier samples.
gpt
--- Reasoning ---
1. Is the question multiple-choice question?
No
2. Is it implied multiple-choice question?
No
3. If two experts were independently asked the question, will the final answer be exactly the same?
Yes

--- Answer ---
grounded