Today's post will cover the last day of the 2017 Hereditary Amyloidosis support group meeting in Chicago. The Sunday agenda is always just half a day, with the doctors answering questions submitted by attendees. The session is moderated by Dr. Gertz, who goes through the stack of questions and decides which questions to ask and which doctor or doctors to give the questions to. I have submitted questions in the past for the Sunday session, and I submitted a two-part question this time as well.
If you recall from my blog post about the Saturday presentations, Dr. Benson did discuss the difference in numbers (when referring to a specific mutation) when the full length of the protein (including the signal peptide) is considered vs. when the length of the mature protein is considered (not including the signal peptide). He discussed the length of the signal peptide for transthyretin (TTR) which is 20, meaning you just add or subtract 20 to get from one number to the other. But he did not mention the signal peptide length of the other proteins that can cause hereditary amyloidosis, such as fibrinogen, lysozyme, apolipoprotein, or gelsolin. When the report from the nomenclature committee came out last year I looked up somewhere that the length of the signal peptide for fibrinogen was 19, not 20 like TTR. I don't recall what the length is for the other rare ones, but if I remember correctly they are not 20 either. Since I would not want anyone leaving the meeting thinking their signal peptide length was 20 when it is really something else (knowing very well that I was probably the only person there who cared), I submitted two related questions:
Question 1: What is the signal peptide length of the amyloidogenic proteins other than TTR?
I was hoping the question would go to Dr. Benson and he would say the signal peptide length is 20 for TTR but it is 19 for fibrinogen, xx for apolipoprotein, yy for lysozyme, etc., and then talk about how confusing it will be to get everyone on the same page. That leads to my second question:
Question 2: Will Dr. Benson promise not to retire before everyone is comfortable with the new recommendations of the nomenclature committee?
For those of you who don't know, Dr. Benson is probably past normal retirement age. He received his bachelor's degree in 1961 and his MD in 1965, so he has been practicing medicine for over 50 years. Given his expertise and experience, especially in discovering many of the mutations that cause hereditary amyloidosis (including some of the fibrinogen mutations), his retirement will likely have a huge impact on both patients and doctors in the amyloidosis community. So my second question was obviously intended to bring a little levity to the proceedings. Dr. Benson has a very quick wit and a dry sense of humor, so I felt certain he would have an entertaining answer to the question.
With so many attendees at this year's meeting, Muriel announced before the session started that if they did not get to all of the questions they would try to get answers later and make those answers available in a document they would let everyone know about. Typically she will publish all of the answers from the Q and A session, but as of this writing she has not. If and when she does I will update this post and also mention it in the next new post.
So the Question and Answer session starts Sunday morning, with Dr. Gertz reading the questions out loud and then having the appropriate doctor answer them. As usually happens during the Sunday session, some doctors need to leave before the session is over at noon in order to catch their flights back home. As the morning went on, a few doctors got up from their seats in the front of the room and started walking down the center aisle toward the exit at the back. Dr. Gertz would notice the doctor leaving and say something like "Thanks to Dr. So-and-so," prompting the audience to give that doctor a round of applause. Well, much to my surprise, Dr. Benson got up and left at some point before 10 AM. That, of course, means my first question will either not be asked at all or will be answered by one of the other doctors. And if Dr. Benson is not there, there is no point in asking my second question. Well, that was a missed opportunity.
Although most of the questions asked during the Sunday session do not relate to fibrinogen amyloidosis because many of them are questions about symptoms typically not associated with AFib or questions about the drugs for ATTR currently in clinical trials, I do enjoy the Sunday session anyway since I find most of the topics discussed very interesting and informative. It is also interesting to hear different doctors respond to the same question as they all have their unique perspective.
Then much to my surprise, about 20 minutes before the scheduled noon end time, Dr. Gertz must have gotten to the sheet of paper with both of my questions. I heard him read my second question first, somewhat quickly and quietly to himself, and he got a little chuckle out of it. Then he said something about the next question (referring to my Question 1) being for Dr. Benson but he has already gone. A couple of people then spoke up and said Dr. Benson was actually still there, and lo and behold he did make his way from the back of the room to a microphone stand in about the middle of the aisle.
Dr. Gertz asked Dr. Benson my first question about the signal peptide lengths, and he gave a long answer that went into some of the science behind what actually happens with the signal peptide. But he did eventually get around to the point that with TTR it's easy to do the math because you just add 20, whereas with something like fibrinogen "I have to get out my calculator because I have to add 19." I don't think he mentioned the lengths of any of the others, but I was glad he at least confirmed what I thought I knew about fibrinogen. Unfortunately Dr. Gertz did not ask Dr. Benson my second question at this point, which is too bad. He was probably trying to get a few more questions answered since he was running out of time.
Since the subject of nomenclature and this numbering scheme can lead to some confusion due to the different ways a genetic mutation can be written (I have seen the most common AFib mutation written at least three different ways in published medical journal articles), I will go over that in a separate post.
Around noon the meeting ended and we all had lunch, which included cookies for dessert because Dr. Benson had asked Muriel Finkel specifically for that. Cathy and I then said our goodbyes to Cathy T. and Lon before heading to the airport to catch our flight back home. We had a few hours before our flight, so I took Cathy on the full tour of O'Hare Airport since she had never been there before. If you ever have time to walk around inside O'Hare Airport in Chicago, do it. Much of it is just like any other airport, but there are a few interesting things to see.
That wraps up the 2017 Hereditary Amyloidosis meeting in Chicago. There was an evaluation sheet we completed after the meeting, and one of the questions asked where we would like to see the next meeting held in 2019. The choices were Chicago, Phoenix, Baltimore, Jacksonville, and Salt Lake City. I will be surprised if Muriel has it some place other than Chicago, but I suppose she is open to the idea since she asked the question. I plan on being there, wherever it is.