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1398 HUMAN LNIih:Iti’1’INUIay. scheme will to a great extent, on the price at which the various grades can be sold. The price at present demanded for " Grade A (Certified) " under the scheme which the new rules replace is high, and if the price of the cheaper of the new grades-viz., " Grade A " and " Pasteurised "-is seriously above that of ungraded milk, it cannot be expected that they will succeed in driving the latter off the market or make it possible eventually for official action to do so. If, however, these grades can be produced at about the same price as ungraded milk-and we think the " Pasteurised " grade can-the scheme is likely to have a profound influence for the better on our milk sup- plies. It will be interesting to watch whether it will be the Grade A or the pasteurised milk which will eventually gain the public favour and so hold the field. HUMAN INHERITANCE. MORE than ten years ago the issue of pedigrees of i hereditary diseases and anomalies of the eye was T planned as a section of the " Treasury of Human t Inheritance," which had already won a permanent t place in scientific literature. The war interrupted T the work and it is only now, four years after the l Armistice, that it has been possible for publication t to be resumed. The editor, Prof. Karl Pearson, ( writes that he has " waited and hoped in vain for ( a substantial fall in the post-war cost of publishing a work of this kind. The cost is practically three times what it was when the Treasury’ was started, i and it has been necessary to raise the price of issue to a figure which will not be prohibitive of further ( publication." j This volume now before us treats of retinitis pigmentosa and allied diseases, congenital night- blindness and glioma retinae; it is the first part off the Nettleship Memorial Volume and is appropriately prefaced by a graceful and just memoir of Edward Nettleship, by Mr. J. B. Lawford. Edward Nettleship belonged to a class which reflects high honour upon the profession, the class of men whom the heavy claims of professional practice have not deprived of the desire and the power to contribute to the advance- ment of pure science. During the greater part of his life Nettleship was in practice and, moreover, never refused to take his share, or even more than his share, in the administrative and educational work which devolves upon the staff of the teaching hospitals. But his keenness for research was never blunted and, after his retirement from practice in 1902, his store of knowledge was used to such advantage, not only in this work but in the sister volumes on " Albinism in Man," that his election to the fellowship of the Royal Society in 1912 met with universal approbation. Mr. Lawford has given a charming sketch of Nettle- ship’s career, and a sound appreciation of his personal qualities. It is well that such an account of the man should accompany the record of work of which his share was large. Although Nettleship had collected much material for some sections of this volume, more remained to be done, and the work was entrusted to Dr. Julia Bell, under a grant from the Medical Research Council, for whose aid Prof. Pearson expresses his gratitude. Dr. Bell has done her work in a manner which would have secured the approval of Nettleship, than which there could not be higher praise. Retinitis Pigmentosa. The first chapter contains a general account of retin- itis pigmentosa and the conditions which Nettleship regarded as allied-retinitis pigmentosa sine pigmento, retinitis punctata albescens, gyrate atrophy of the choroid and retina, choroideremia. Retinitis pig- mentosa receives most attention. The 20 beautifully clear plates of pedigrees devoted to it include several 1 Treasury of Human Inheritance. Vol. II. : Anomalies and Diseases of the Eye. Nettleship Memorial Volume. Part 1. By Julia Bell, M.A., M.R.C.S., L.R.C.P. Cambridge University Press. 1922. With 26 plates. Pp. 123. Price 45s. fine examples of genealogical research, particularly those due to the labours of Mr. C. 11. Ussher and of Nettleship. Dr. Bell provides a judicial account of the history of opinion respecting the pathology of the condition. She remarks an increasing tendency to regard the defect as a primary atrophy of the retinal elements and refers specially to Mr. Treacher Collins’s paper, wherein he points out that a number of micro- scopic examinations have been made in which the choroid was found to be normal, and suggests that only by a destruction of the rods and cones, leaving gaps in the external limiting membrane through which pigment grains attracted by the action of light may migrate and reach the internal layers of the retina, can the mechanism of pigmentation be explained. The experiments of A. Wagenmann, K. Berlin, E. Kruckmann, and Capauner show that the outer layers of the retina depend upon the choroidal circulation for their nutrition, and that in some animals retinal pigmentation may be produced by interfering with the choroidal circulation; but they do not prove that retinitis pigmentosa of man is primarily due to a defect of the choroidal blood-supply. The work of the Galton Laboratory has shown that in many cases of heritable defects, the number and character of associated defects is remark- able. Often, owing to the fact that the author of the pedigree has made no inquiry respecting other conditions than that studied, no inference can be drawn ; but the work of Ussher is especially valuable, as he systematically elicited information in this respect, while in a large family tree worked out by Nettleship, 19 sibships of which contained affected members, speciat"tíòfÁ3 was made of the fact that no other defect occurred in the stock. On the whole, it appears safe to conclude that retinitis pigmentosa occurs largely as a single defect unaccompanied by any other disability, but that when deafness does occur in association with the defect of the eye, the link is a close one ; the two disabilities may be expected to occur inseparably within the stock. It is not part of the plan of the " Treasury " to enter at large upon statistical discussions, and Dr. Bell only proffers a few suggestions. It appears that 27-2 per cent. of affected individuals are the product of consanguineous marriages ; 25-8 per cent. of affected sibships are of consanguineous parentage. This percentage is very close to the 29 per cent. of albinos of all classes found by Prof. Pearson to result from consanguineous marriages. If one limits the affected population to sibships in which at least one case of deafness also occurs, 40’2 per cent. of the selected persons are sprung from consanguineous parents. It may be remarked that Miss Elderton’s investigations suggest that not more than 3 per cent. of marriages of first-cousins occur in the general population. A very curious point is the following : if only sibships containing affected members are considered, the percentages of affected offspring work out thus : both parents normal and not related, 45-6 per cent.; both parents normal and related, 44-7 per cent. ; one parent affected, no consanguinity, 53-6 ; one parent affected, consanguinity, 50-0. With this may be contrasted Fay’s results on deaf-mutism. According to him, when one or both parents are affected and consanguineous, 30 per cent. of the offspring are affected, when the parents are not akin only 8 per cent. are affected. Prof. Pearson again found that when one parent was albinotic and the marriage was consanguineous 32 per cent. of the offspring were albinotic, but only 14 per cent. when the parents were not akin. When neither parent was albinotic but the parents were akin 40 per cent. of the offspring were affected, when they were not akin only 34 per cent. Of the rarer allied defects, retinitis punctata albescens provides the most pedigree data. Sixteen pedigrees are included ; one of these contains Nettle- ship’s case in which the white dots very well seen at the age of 21 had disappeared from both fundi by the age of 47. The patient was night-blind as long as he could remember, and this condition did not change.
Transcript
Page 1: HUMAN INHERITANCE.

1398 HUMAN LNIih:Iti’1’INUIay.

scheme will to a great extent, on the price atwhich the various grades can be sold. The price atpresent demanded for

" Grade A (Certified) " underthe scheme which the new rules replace is high, andif the price of the cheaper of the new grades-viz.," Grade A " and " Pasteurised "-is seriously abovethat of ungraded milk, it cannot be expected thatthey will succeed in driving the latter off the marketor make it possible eventually for official action to doso. If, however, these grades can be produced at aboutthe same price as ungraded milk-and we think the" Pasteurised " grade can-the scheme is likely to havea profound influence for the better on our milk sup-plies. It will be interesting to watch whether it willbe the Grade A or the pasteurised milk which willeventually gain the public favour and so hold the field.

HUMAN INHERITANCE.

MORE than ten years ago the issue of pedigrees of i

hereditary diseases and anomalies of the eye was Tplanned as a section of the " Treasury of Human

t

Inheritance," which had already won a permanent tplace in scientific literature. The war interrupted Tthe work and it is only now, four years after the lArmistice, that it has been possible for publication tto be resumed. The editor, Prof. Karl Pearson, (writes that he has " waited and hoped in vain for (a substantial fall in the post-war cost of publishinga work of this kind. The cost is practically threetimes what it was when the Treasury’ was started, iand it has been necessary to raise the price of issue toa figure which will not be prohibitive of further (publication." j

This volume now before us treats of retinitispigmentosa and allied diseases, congenital night-blindness and glioma retinae; it is the first part offthe Nettleship Memorial Volume and is appropriatelyprefaced by a graceful and just memoir of EdwardNettleship, by Mr. J. B. Lawford. Edward Nettleshipbelonged to a class which reflects high honour uponthe profession, the class of men whom the heavyclaims of professional practice have not deprived ofthe desire and the power to contribute to the advance-ment of pure science. During the greater part of hislife Nettleship was in practice and, moreover, neverrefused to take his share, or even more than his share,in the administrative and educational work whichdevolves upon the staff of the teaching hospitals. Buthis keenness for research was never blunted and, afterhis retirement from practice in 1902, his store ofknowledge was used to such advantage, not only inthis work but in the sister volumes on " Albinismin Man," that his election to the fellowship of theRoyal Society in 1912 met with universal approbation.Mr. Lawford has given a charming sketch of Nettle-ship’s career, and a sound appreciation of his personalqualities. It is well that such an account of the manshould accompany the record of work of which hisshare was large.

Although Nettleship had collected much materialfor some sections of this volume, more remained to bedone, and the work was entrusted to Dr. Julia Bell,under a grant from the Medical Research Council, forwhose aid Prof. Pearson expresses his gratitude.Dr. Bell has done her work in a manner which wouldhave secured the approval of Nettleship, than whichthere could not be higher praise.

Retinitis Pigmentosa.The first chapter contains a general account of retin-

itis pigmentosa and the conditions which Nettleshipregarded as allied-retinitis pigmentosa sine pigmento,retinitis punctata albescens, gyrate atrophy of thechoroid and retina, choroideremia. Retinitis pig-mentosa receives most attention. The 20 beautifullyclear plates of pedigrees devoted to it include several

1 Treasury of Human Inheritance. Vol. II. : Anomaliesand Diseases of the Eye. Nettleship Memorial Volume.Part 1. By Julia Bell, M.A., M.R.C.S., L.R.C.P. CambridgeUniversity Press. 1922. With 26 plates. Pp. 123. Price 45s.

fine examples of genealogical research, particularlythose due to the labours of Mr. C. 11. Ussher and ofNettleship. Dr. Bell provides a judicial account of thehistory of opinion respecting the pathology of thecondition. She remarks an increasing tendency toregard the defect as a primary atrophy of the retinalelements and refers specially to Mr. Treacher Collins’spaper, wherein he points out that a number of micro-scopic examinations have been made in which thechoroid was found to be normal, and suggests thatonly by a destruction of the rods and cones, leavinggaps in the external limiting membrane throughwhich pigment grains attracted by the action of lightmay migrate and reach the internal layers of theretina, can the mechanism of pigmentation beexplained. The experiments of A. Wagenmann, K.Berlin, E. Kruckmann, and Capauner show that theouter layers of the retina depend upon the choroidalcirculation for their nutrition, and that in someanimals retinal pigmentation may be produced byinterfering with the choroidal circulation; but they donot prove that retinitis pigmentosa of man is primarilydue to a defect of the choroidal blood-supply.The work of the Galton Laboratory has shown

that in many cases of heritable defects, thenumber and character of associated defects is remark-able. Often, owing to the fact that the author ofthe pedigree has made no inquiry respecting otherconditions than that studied, no inference can bedrawn ; but the work of Ussher is especially valuable,as he systematically elicited information in thisrespect, while in a large family tree worked out byNettleship, 19 sibships of which contained affectedmembers, speciat"tíòfÁ3 was made of the fact that noother defect occurred in the stock. On the whole,it appears safe to conclude that retinitis pigmentosaoccurs largely as a single defect unaccompanied byany other disability, but that when deafness doesoccur in association with the defect of the eye, thelink is a close one ; the two disabilities may be expectedto occur inseparably within the stock.

It is not part of the plan of the " Treasury " toenter at large upon statistical discussions, and Dr.Bell only proffers a few suggestions. It appears that27-2 per cent. of affected individuals are the productof consanguineous marriages ; 25-8 per cent. of affectedsibships are of consanguineous parentage. Thispercentage is very close to the 29 per cent. of albinosof all classes found by Prof. Pearson to result fromconsanguineous marriages. If one limits the affectedpopulation to sibships in which at least one case ofdeafness also occurs, 40’2 per cent. of the selectedpersons are sprung from consanguineous parents. Itmay be remarked that Miss Elderton’s investigationssuggest that not more than 3 per cent. of marriagesof first-cousins occur in the general population. Avery curious point is the following : if only sibshipscontaining affected members are considered, thepercentages of affected offspring work out thus : bothparents normal and not related, 45-6 per cent.; bothparents normal and related, 44-7 per cent. ; one

parent affected, no consanguinity, 53-6 ; one parentaffected, consanguinity, 50-0. With this may becontrasted Fay’s results on deaf-mutism. Accordingto him, when one or both parents are affected andconsanguineous, 30 per cent. of the offspring are

affected, when the parents are not akin only 8 percent. are affected. Prof. Pearson again found thatwhen one parent was albinotic and the marriage wasconsanguineous 32 per cent. of the offspring werealbinotic, but only 14 per cent. when the parentswere not akin. When neither parent was albinoticbut the parents were akin 40 per cent. of the offspringwere affected, when they were not akin only 34 percent. Of the rarer allied defects, retinitis punctataalbescens provides the most pedigree data. Sixteenpedigrees are included ; one of these contains Nettle-ship’s case in which the white dots very well seen atthe age of 21 had disappeared from both fundi bythe age of 47. The patient was night-blind as longas he could remember, and this condition did notchange.

Page 2: HUMAN INHERITANCE.

1399MEDICINE AND THE LAW.

Congenital Stationary Night-Blindness.The second section of the monograph is devoted

to congenital stationary night-blindness; of the 33pedigrees 19 belong to the sub-group in which bothsexes are affected, 14 to that in which males only ’,are affected, but the condition is usually transmittedthrough the female line. " Nowhere," remarks Dr.Bell, " do we realise our debt to Nettleship morekeenly than here ; if we omitted the pedigrees whichhe worked out or which were investigated owing to hisenquiry we should, indeed, find ourselves with scantyinformation." Indeed, the Cunier pedigree of theNougaret family as extended by Nettleship’s researchesis probably the most complete example of genealogicalresearch in medicine which we possess. In the formaffecting both sexes, there is evidence that consan-guineous marriages have some setiological significance,but it does not appear that the percentage of affectedoffspring is higher amongst the issue of such marriagesthan in other tainted stocks. In the form limited tomales, consanguinity does not seem to play a r6le.

Glioma Retince.The concluding section of the work deals with the

rare and malignant condition now termed gliomaretinae, the fungus hsematodes of the older writers.Since, on the basis of the data presented by suchwriters as H. Wmtersteiner, C. Adam, U. Vetsch, Plant,.A. v. Graefe, Trantas, L. Caspar, E. Stieren, Lowtzow,and Alvarado, glioma retinae does not account formore than 0 -03 per cent. of all patients afflicted with eyediseases, the significance of multiple cases in the samefamily is obvious. Dr. Bell has been able to collect36 small family histories, giving records of 128 cases,each of which belongs to a stock in which one

or more further cases of the disease occurred. Thelargest series in one sibship is that of R. E. Newton,where 10 members of a,.-.ID.bshlp of 16 were affected.J. Thomson and H. Knapp’s case is striking. Fiveout of 14 children of one family were affected, also amale cousin on the father’s side, while an aunt of thefather had had two children who died of the disease.The material is too scanty to permit of statisticalinferences being drawn.To those not specially interested in the science of

statistics nor much attracted by genealogical diagramsthe title of this work may not appeal. If, however,they can be tempted to open the pages they will findin them much which cannot fail to interest anyeducated man. Those who are versed in the scientificstudy of inheritance need no commendation from usto encourage them to ponder this latest contributionto medical literature. Prof. Karl Pearson and Dr.Julia Bell have erected a worthy monument to thememory of a great ophthalmologist.

MEDICINE AND THE LAW.

Medical Referees and their PrÙ.:ate Practice.IN the House of Commons a question was asked

recently as to whether it was in order for a man toact as medical referee who had previously acted inthe same case and in a private capacity for employeror employee. Further questions were added as tothe result of such action as above, and as to thedesirability of the appointment of a sufficient numberof medical referees to prevent any such being expectedto be a referee in a case as to which he had alreadybeen consulted. The answer to the first questionwas so obvious that it seems hardly necessary tohave asked it, even in order to pave the way for theothers. It needed no great prevision on the part ofthose responsible for the Workmen’s CompensationAct, 1906, to insert in it Section 10 (1): " Where amedical referee has been employed as a medicalpractitioner in connexion with any case by or onbehalf of an employer or workman by any insurersinterested, he shall not act as medical referee in thatcase." This governs the matter, apart from whichit would seem that the sense of justice and prudence

of any medical practitioner would cause him to refuseto appear in any case in the dual capacity suggested.The answer of the Home Secretary stated the opinionthat if a medical referee acted contrary to the pro-hibition in the Act, his decision would not be binding ;the Home Secretary added that he was always readyto consider representations as to the needs of a par-ticular district for more referees, while he had no reasonto think existing appointments insufficient. Themember who asked the question did not specify theoccasion or locality to which he was referring, but itmay be suggested that if any such occasion as hedescribed should arise, or that if anywhere thereshould be a shortage of medical referees, the trade-unions and employers’ associations of the district, orfor that matter the county-court judge in whosecircuit the matter arose, could press for a remedyby making representations to the department con-

cerned. Redress would in this way be more speedythan by means of a question in Parliament.

The Defence of Insanity.The Court of Criminal Appeal had before it two

appeals by men both sentenced to death for murderat Lincoln assizes, on behalf of each of whom at histrial the defence of insanity had been set up. Oneof them, named Robinson, had killed a girl namedPacey with whom he had been in love, cutting herthroat, and then inflicting wounds on himself, afterwhich he had thrown himself into a pond. He had,however, got out of the pond unaided and gone hometo bed. The Lord Chief Justice stated as the con-clusion of the court that the case had been laid fullybefore the jury by the judge at the trial, and thatthere was no reason for the Court of Criminal Appealto interfere. He referred to medical evidence, whichhe said was to the effect that Robinson might havebeen insane, but the question for the jury was whetherthey were satisfied that he was insane. The defenceof insanity was, he added, becoming an invariablemakeweight in trials for murder, and it was right thatit should be scrutinised with care by juries. In theother case the prisoner, Frank Fowler, went into aninn at Warwick Deeping in which there were severalpersons, and shot and killed a girl named Ivy Prentice,who had been married three days before. There wasevidence that Fowler’s father was mentally defective,and other evidence as to acts of his own on which thedefence relied to show that he was not of ordinarymentality. In giving judgment the Lord ChiefJustice said that the description given of Fowler wasthat he was a surly man, but that his intelligence wasnot below that of the ordinary villagers around him.The jury had been clearly directed on the law, andhad heard the evidence summed up, and upon it itwas open to them to return a verdict of guilty. Thecourt could not revise the verdict merely because itmight have come to a different conclusion from thatat which the jury had arrived. There must be some-thing to show that the questions at issue had not beenput properly before the jury. These cases will benoted, no doubt, by those who consider that the rulein MacNaughten’s case should be revised. Thisappears to be a view not held by many judges.During the hearing of Fowler’s appeal a reference tothe case of Ronald True drew from Mr. JusticeDarling the observation that that case must not betaken as a precedent.

PARSONS FELLOWSHIP AT GUY’S HOSPITAL.-Agift of .B2600, to be paid in instalinents of ,e-100 a year overa period of six and a half years, has been made by thedirectors of Ashton and Parsons, Ltd., to Guy’s Hospitalto be spent in research on diabetes mellitus and otherrelated diseases of metabolism, in the medical investigationdepartment of the medical school. The money will beused to found a Parsons Fellowship and wili provide forthe services of an additional worker to aid in the investiga-tions into the preparation and use of "insulin," the newsubstance discovered by Banting and Best at TorontoUniversity. Guy’s Hospital is one of the institutions atwhich combined research on this subject is being undertakenunder the auspices of the Medical Research Council.


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