 We'll ask our panelists if they have any questions or comments for dr. Plowman. Oh, I'll start out I keep thinking about the fact that parents have their own genetics and They don't pass them all on to their children. There's only 50% similarity, right? It sounds to me as though you're saying The only thing that matters about parenting is whatever the genetics of the child have elicited from them as though there was no independent effect of the parents own individual variation based on genetics and their own life experience So because you've emphasized so heavily the eliciting function of the child I wonder if you'd say something about that. Sure. I think part of the problem is that In a talk like this where if you think it was too long, it was whittled down about two-thirds from what I started with You know, you're kind of forced to emphasize certain aspects of it And what's it's not very novel to say parents affect kids environmentally, which is what you're going to talk about tomorrow but I was trying to say that parents Parenting does correlate with the kids outcomes and what's novel is to realize that there's some genetic Mediation of that and but I'm not trying to say that it's all genetic But I am trying to say that given that design It's most likely the way that's going is that parents are responding to genetic differences in the kids Because in that study in most of these studies the twins are kids It's a children twins as children's design But in Sweden now David Reese has gone on to do the complementary design to get parents who you know Average age 40 who are twins who have children who are adolescents Because that's parents as twins design and that would emphasize the genetic influence on the parenting More independent of the kids and people have been doing that haven't you or have you done it yet? Well, that study's been going on for probably six years or so eight years or so and there are some reports coming out from it That also suggests that if you look at parents as twins, there's genetic influence on parenting, but again It's not to say it's all genetic. There's a strong environmental component to all of this and Eleanor's You know may a copa. I was when I just I was looking at my watch and noticing I was behind schedule So when I got to that last part of my talk Saying to what extent is there genetic? Mediation of parenting as it relates to kids outcome. I only emphasize the genetic Mediation and that example I gave you was the one that showed the strongest genetic mediation There are many other examples where genetic mediation was much weaker So the news is there's genetic mediation there, but I shouldn't take away from the fact that a lot of the relationship is Environmental as you'd expect it to be, but I'm sure you'll redress the balance tomorrow Dr. Kagan I don't mean this to be a technical point But I think it's important in human development So children only Since once you get to be 18 months you're thinking and therefore you're constantly comparing yourself with all your siblings and your relationship I don't think there can be any share environment and that it's always shared Because in humans unlike animals You are conceptualizing your role And and so the question to you is do you really think you can have any variance for shared environment for psychological traits? I don't think there can be any share environment I would argue that most developmentalists assume that environmental variation is shared And I know we'll get some disagreement on that, but it was only the clinicians I know of who focused on difference differences and experiences among children in a family They would talk about processes like scapegoating for example Where one child is you know scapegoated for problems in a family But people haven't studied the environment that way as if they recognize that what's ever going on is Experience differently by two kids in a family. I'll give you some examples that I think are are really very shocking like asthma Do you know asthma is highly heritable? There's been half a dozen twin studies in recent years in early childhood Asthma is highly heritable like The environmental influences are completely non-shared Adoptive siblings correlate zero for for that for asthma, but what are our theories of asthma? The big theories are pollution. It's like how near to a motorway you live Well two kids in a family live near to the same motorway So this non-shared environment points to new ways of thinking about the environment like with asthma What's important is not what two kids in a family share? Whatever it is environmentally It's what makes two kids in a family So if you recognize that that's the key then it seems to me you'd want to study differences within a family No Let's go on one second. We agree completely My question is that you do want to study the family. Mine was a theoretical question Robert That I don't see any defense for human psychological traits for two or more children of the notion of shared environment That it's never shared because the children are conceptualizing their properties their Relationship to their parents and in their heads. They are not in the same environment None non-shared environment is powerful. I don't believe there's any shared environment for human psychological traits That's what I'm saying Well, I Doubt that that's the story we'll get tomorrow. Would you say I'm having so much trouble here? It is difficult to hear each other Maybe we should just go on. Okay. Hello. I like this Here's a question from the audience Would the panel comment on studies that support the proposition that the greatest environmental influence on children's development? Is peer relationships not parental influences? Oops I don't know if this is an extremely clever question, but an issue I skated over in terms of non-shared environment is a book in 1998 by Judith Harris called the nurture and the nurture assumption being this assumption that Unlike Jerry, I think Judith Harris says most people assume that the important environmental Influences are those early in life that ought to be shared by two kids growing up in the same family because I mean you do experience The same parents I take Jerry's point exactly though. Do you experience the same parents? Yes, you have the same parents, you know and say if they go through divorce. Well, you've had divorce, right? Well, not necessarily Can experience divorce of the family of the parents very differently. So anyway Judith Harris Her book was emphasizing the importance of non-shared environment really the topics of my talk Nature of nurture and non-shared environment and the novel aspect of her book though was to say that those of us who Were looking at the family environment for non-shared environment were barking up the wrong tree at the end of our NEA D study we had to conclude that the family environment when you control for genetics wasn't really the source of non-shared environment Not much so Judith Harris is saying that peers are where it's at because siblings do to a large extent experience different peer groups now there That hasn't been tested much There's a couple of studies now that are suggesting that yes peers do account for some of the non-shared environment But it's probably not the silver bullet that explains everything well when it comes to Designs that aren't genetically sensitive. You certainly can see very large socialization When it comes to gender differentiation So I don't think there's anything wrong with thinking that there is pure influence I just don't think it means that there's very little parent interference influence Okay, that's another question from the audience With what degree of certainty can we say that the genetic identity of identical twins is absolute? Yeah, there's been a lot of talk about different types of twins, but now with DNA work all of our twins our routine Markers where you get We typically use a bank of 12 DNA markers and we just do this through the mail actually You know you just have a q-tip and you rub the inside of your mouth and you can get enough DNA there to do hundreds of DNA markers so we routinely then put all of our twins through a Multiplex it's called one one go and you genotype these dozen or so highly informative markers it's sort of what in a way what DNA fingerprinting is about and identical DNA Eric Kandel made an important point, but just in passing and that is he The environment doesn't change our DNA there can be mutations but what he was talking about are changes in gene expression and That's a hugely important area of research But the neat thing about studying DNA is that DNA is causal Everything else we study in biology neurotransmitter levels or whatever it's correlational when you show that a neurotransmitter level correlates with anxiety As Eric Kandel and Jerry were saying it can be behavior causing the biology, but with DNA Its correlations are causal because nothing changes that DNA Structure and so identical twins are identical except for rare mutations There's one one pair of identical twins who are opposite in sex Believe it or not because it's actually just one gene this one region on the Y chromosome That's sex determining and there was a mutation very early Twin pair so yeah, you can get these very aberrant situations where identical twins are differed genetically, but after looking at Really thousands of pairs of twins the identical twins don't differ on a single bit of DNA even if you sequence them Do you believe that the lack of heritability in many disorders Lessens the necessity of testing for illnesses within families less makes it less necessary to look for apparently family histories or Well with breast cancer is a sad case in a way because GPs were just sort of getting the message there's genetic influence and they ought to screen for it if women go to the GP They will when they're asked about their family history they'll be I get asked about breast cancer But unfortunately, that's one of the least heritable characteristics around and but it's probably worth asking about even though It's the least heritable characteristic because there we do You know there's huge issues right now What if you are one of those one or two percent of women who have that particular? BRCA one or two where you are at risk for that very early onset very severe Bilateral usually ovarian cancer. It's a very nasty cancer if you could predict it early There are options that you have they're not happy options, but It's probably you know worth knowing about it even in a case where it's not very highly heritable like breast cancer But in general most is useful stay in the case of alcoholism You know even though it's you have it's like a five-fold greater risk if you have a first-degree relative who's alcoholic And so it doesn't mean you're going to become alcoholic But it means if you go out and drink as much as your your mates do you're more likely to become alcoholic than them And so it's probably worth knowing that and it's I would say Makes it more important to be screening for these traits Another one here Well, you know anybody who's done that In England much to my surprise. There's a person. Unfortunately. You just died recently no connection I'm sure who really says there's no such thing as talent musical ability, especially and I in getting involved in that a bit. I've been quite struck by an important point This is related to the is jeans destiny I have a friend Nick Youth orchestra where they take young talented people and give them, you know terrific Chances over a summer to work with the best conductors. He's convinced you can take song with essentially no talent and make them into a professional musician But in that same cohort you'll find some kids who are just mind-bogglingly good and with the same amount of training they're off the scale And so I think that's largely what it's about That there certainly are genetic contribution It's amazing how far we can go environmentally Okay, well one last questions. We don't have our ethicist here I'll count on the audience here to provide the ethical question Can scientists afford the old-fashioned view of separation of science and politics and democracy? Given the ways in which decisions are made don't science scientists have an obligation to anticipate the way Their work will be taken up for example genetics greening gets used by insurance Certainly deferred to my more senior colleagues on this question. I mean my View on it is I'm glad to be working in an area of behavioral sciences where people care I mean, you know where you could do damage. I want to do dangerous science I want to do science that can make a difference so much of Behavioral science nobody ever reads or cares about so this issue of nature and nurture is important to people Which is why we have to worry about how these results are used. I can't recommend strongly enough though These are just the sorts of issue. He's dealing with but basically you can see backpedaling and copping out here to defer to My colleagues here because these aren't issues, you know that are specific to me correct and dr. Kagan is eager to jump in here At my old age, this is the one issue that still generates a great deal of passion In the evolution of our species as we all know some and we developed an ethical sense It's part of our genome and that changed all the rules Because our ethical sense Moves us to our ideas of justice and equality and taking care of the weak and Therefore it is very dangerous as many people have said bitkenstein said it beautifully when it comes to ethics It's totally independent of facts and so Science is beautiful We've had a wonderful day and tomorrow. We will have an equally beautiful day helping us understand Ourselves and the world my god It's perfectly lovely. Let's not get greedy humans want to believe that their politicians and The people in power are using something rationally because as we all know That position of privilege has changed in the 10th century the church decided What was what shall be the law of the land? They advised the kings and philosophers took over and This is not meant as either negative science is now the Arbitra and therefore the average citizen Until decisions being made in state houses or in Washington But then let science be the arbiter. It has to be based on something on a position that has the privilege of power and truth and I think that is very dangerous Look, let's take one example look like many I believe that there's no question that Adult men Pre-disposed to mate with many women in other words that adultery is in our biology But that does not mean that in a November referendum which said Since we have learned from biology That adult men are strongly disposed by their genes To be adulterous Should this not be a crime? I think Americans in their wisdom in the last point and in doing that They are not being silly Irrational or sentimental what they're saying is Mr.. And Mrs.. Scientist that is a very interesting fact Really interesting I Choose not to use it in running my society. That's perfectly rational We'll give Eleanor the last word since I am the most senior of your colleagues here I'd like to say a little bit about my experience doing work on gender differentiation I have had people say to me Do not publish that finding that will be damaging to the cause of women and I had who is a hot feminist. I'm a feminist myself, but not quite as hot as she and We agree we will not suppress any findings Because ultimately the truth will make us free and I believe that is so and that that societies can make more intelligent decisions as you say Jerry They may decide to ignore some truths They probably in the long run will do better if they build up. I want to argue for science and I don't mean to say let politics go whichever way it wants to I think that We care very much about what the applications of what we find are but that doesn't mean we ever distort them With that note, I believe we'll let our panel go home and rest up for tomorrow. Thank you tomorrow morning