Aspects of genetics in paediatrics : scientific proceedings of the 3d Unigate Workshop held at the Royal College of Physicians, St. Andrew's Place, London, May 1975 / edited by Donald Barltrop.

  • Unigate Paediatric Workshop 1975 : London, England)
Date:
1976
Catalogue details

Licence: Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)

Credit: Aspects of genetics in paediatrics : scientific proceedings of the 3d Unigate Workshop held at the Royal College of Physicians, St. Andrew's Place, London, May 1975 / edited by Donald Barltrop. Source: Wellcome Collection.

    68/136 (page 56)
    56 Discussion uncomfortably rare, but we have sufficiently strong data to show that their performance score is invariably poorer than their verbal score. If one contemplated doing something remedial on these children, who after all are relatively easily diagnosed, it would be very valuable. Childs : I agree. If those children are not able to find their way home, it would seem to me important that people knew that they cannot find their way home. The same applies to people who cannot calculate—who cannot do arithmetic. PoLANi: One other group is speech retardation. Harris: You spoke of people who cannot calculate. There are other people at the extreme end who can calculate remarkably well, they are high-powered mathe¬ maticians. Perhaps they could be picked out and studied from this point of view. Whether they have a continuous gradation, or whether there is a phenotype to be identi¬ fied, I do not know. PoLANi : Finger numbers is another example that comes to mind. You say, 'Where is number IT, and they say there, and you say, 'Where is number 5?', and they say there. Childs: Galton I believe studied that himself. People were said to have curious mental images of numbers. One speaks of using Galtonian methods to study be¬ havioural variability, but Galton was more interested in the individual than he was in the distributions. Oppé: Are there not two sorts of 'other ends'? There is the person who cannot calculate and then there is the genius who can calculate. Dr McClearn's mice went from the hyperactive to those who were paralysed on one particular square. Would you say that the hypercalcula- tion people were pathological or just at the excellent end of the scale? Childs: Pathological is a loaded word. We are all pathological about something. We should think in terms of normal variability for people who have reading dis¬ ability and the like. McClearn: The middle of the distribution should not be completely ignored. The people who developed IQ testing in general were not as ignorant of, or as disin¬ terested in, individual diflferences as many of their psychological comments. There is a group within the differential psychologists for whom individuality and individual differences are important. Unfortunately, while the IQ tests which are so frequently used have certain merits in terms of academic prediction, they are not very useful as research instruments. The middle of the range could be used in properly designed experiments to obtain a better idea of what the phenotype is that we are seeking. For example, a large-scale population study in which individual cognitive factors were assessed and genetic correlations sought would, with a sufficiently large sample, give us some answers about the structure of cognition. In other words, we would get some notion of whether there is a general factor underlying intellectual prowess. Childs: Is that not what Guilford is trying to do? McClearn: Guilford has never tried to do it with genetic correlations. There are many schools of thought about whether there is a G factor and S factor, but I am proposing that by putting a genetic handle on the re¬ search the issue mi^t be resolved more efficiently. Stroud: There is a large area which we have left completely untouched which is perhaps more important than reading difficulties and learning difficulties, namely what we vaguely call personality. It is important as to whether there is any genetic factor in the inheritance of personality, but it is difficult to define. Many of us deal with what we consider to be a very disprivileged popula¬ tion. In this country we have the phenomenon of large numbers of West Indians who are never able to get to a grammar school. In three medical schools south of the river there is not a single West Indian medical student being trained to be a doctor. There is a general impression that personalities do run in families, but does this have any genetic basis? Secondly, is it possible to use some¬ thing other than learning ability and reading ability? For instance, in our department Margaret Pollak is exposing non-readers to pattern recognition and finding that she can identify slow readers and non-readers without their reading to her at all. It is hoped to apply this to younger age groups to identify them earlier than has hitherto been possible. Childs: I hope you will do a family study. This is exactly the kind of phenotype to use. Stroud: Many of the children are West Indians and their problems may be environmental rather than genetic. Personality is very important because, coupled with intellectual ability, it ultimately determines achievement. Childs: I did not mean to imply that any limit be set on the kind of phenotype that could and should be studied. I emphasized schizophrenia, depression, and reading disability because they are there and because they are the most feasible phenotypes to use. The genetics of personality is infinitely more difficult to study than intelligence. Studies of personality that have been done have used concordance rates for twin pairs. Inheritability calculated in that way is of the order of 0-2 or less, whereas for intelligence it is 0-8 and for schizophrenia it is 0-5-0-8. Perhaps the way to start would be to find some kind of attributes of personality. It seems to me that personality is the product of what we begin with and what experiences we have had. Perhaps we are studying personality if we study things like learning disability or the response to the test you described. Visually evoked responses to light flashes and words are studying per¬ sonality in that the personality is the product of all these things together. One would have far more success in some kind of long-term assessment of what personality might be if one started in simple-minded ways with, say, psychometric tests and looking at the failure of people and so on. Personality may be formed in important ways by an inability to learn to read easily, too. Renwick: Is there any explanation of the mechanism in the very simple case of Lesch-Nyhan syndrome where you have a behavioural phenomenon of a quite striking nature and a relatively simple biochemical defect? No link between the biochemical defect and the simple behavioural pattern has yet been established. Childs: That behaviour is extremely complicated because if those children are restrained they do not want to eat themselves. They like to be restrained because they can be calmed, whereas if they are not restrained it is then that they show this incomprehensible behaviour.