FOUNDATIONS FOR SEX 



63 



27. Ferguson-Smith, Johnston and Handiiiaker, 196( 



28. Book and Santesson, 1960. 



29. Harnden and Armstrong, 1959. 



30. Hungerford, Donnelly, Nowell and Beck, 1959. 



31. Ferguson-Smith, Johnston and Weinberg, 1960. 



32. deAssis, Epps, Bottura and Ferrari, 1960. 



33. Gordon, O'Gorman, Dewhurst and Blank, 1960 



34. Hirschhorn, Decker and Cooper, 1960. 



35. Sasaki and Makino, 1960. 



36. Bloise, Bottura, deAssis, and Ferrari, 1960, 



37. Fraccaro, Kaijser and Lindsten, 1960c. 

 37a. Fraccaro and Lindsten, 1960. 



38. Fraccaro, Ikkos, Lindsten, Luft and Kaijser, 1960. 



39. Harnden, 1960. 



40. Ferguson-Smith and Johnston, 1960. 



41. Sandberg, Koepf, Crosswhite and Hauschka, 1960. 



42. Hayward, 1960. 



it should be remembered that they were 

 sought in institutions for which this is a 

 criterion of admittance. Their mental abil- 

 ity was distinctly less than that of Kline- 

 felter XXY cases which have come under 

 study. The pattern of the XXXY effects on 

 the reproductive tract, however, was com- 

 parable with that observed in the XXY 

 genotypes. The effects of one Y chromosome 

 were balanced by either two or three X 

 chromosomes to give nearly equal pheno- 

 typic effects. 



9. XXY + 66 Autosome Type 



XXY + 66 autosome type was estab- 

 lished by Book and Santesson (1960) for 

 an infant boy having several somatic anom- 

 alies which may or may not be relevant to 

 the sex type. Externally the genitalia were 

 normal for a male of his age, penis and 

 scrotum with testes present in the scrotum. 

 Again the Y chromosome demonstrates its 

 male potencies over two X's even in the 

 presence of three sets of autosomes. The 

 case is of particular significance since fur- 

 ther development may indicate what male 

 potencies an extra set of autosomes may 

 possess. 



10. Summary of Types 



Other types of sex modifying chromo- 

 somal combinations and their contained 

 genes have been observed particularly as 

 mosaics or as chromosomal fragments added 

 or substracted from the normal genomes. 

 No doubt other types will be discovered 

 during the mushroom growth of this period. 

 Time can only test the soundness of the 

 observations for the field of human chro- 

 mosomal genetics and cytology is difficult 

 at best requiring special aptitudes and ex- 

 perience. Mistakes, no doubt, will be made. 

 The status of the subject is summarized 

 in Table 1.5. 



11. Types Unrelated to Sex 



Other cases not related to sex or only 

 secondarily so were scrutinized during the 



course of these studies. The information 

 gained from them is valuable as it strength- 

 ens our respect for the mechanisms in- 

 volved. The sex types which are dependent 

 on loss or gain of the X and/or Y chromo- 

 somes belong to the larger category of 

 monosomies or trisomies. Numbers of auto- 

 somal monosomic and trisomic syndromes 

 have also been identified in the course of 

 these investigations. Similarly, not all cases 

 that have been studied have turned out to 

 be associated with chromosomal changes. 

 This in itself is important since it lends 

 confidence in those that have, as well as 

 redirects research effort toward the search 

 for other causes than chromosomal mis- 

 behavior. The first trisomic in man was 

 identified through the study of Mongolism. 

 The condition affects a number of primary 

 characteristics but not those of sex, for 

 males and females occur in about equal 

 numbers. The broad spectrum of these ef- 

 fects points to a loss of balance for an 

 equally extensive group of genes in the two 

 sexes. The common association of charac- 

 teristics making up these Mongoloids, to- 

 gether with their sporadic appearance and 

 their change in frequency with maternal 

 age, all suggest the findings which Lejeune, 

 Gautier and Turpin (1959a, b) and Lejeune, 

 Turi)in and Gautier (1959a, b) were able 

 to demonstrate so successfully. They estab- 

 lished that the tissue culture cells of Mongol- 

 oid imbeciles had 47 chromosomes and that 

 the extra chromosome was in the small 

 acrocentric group. Lejeune, Gautier and 

 Turpin (1959a, b) have now confirmed 

 these observations on not less than nine 

 cases. Jacobs, Baikie, Court Brown and 

 Strong (1959), Book, Fraccaro and Lind- 

 sten (1959) and Fraccaro (cited by Ford, 

 1960) as well as later observers have sub- 

 stantiated the results on more than ten 

 other cases. The well known maternal age 

 effect, whereby women over 40 have a 

 chance of having IMongoloid offspring 10 

 to 40 times as frequently as those of the 

 younger ages, would seem to point to non- 



