The Authors report a case of translocation 21/21 in a woman who, after two miscarriages, gave birth to a mongoloid daughter — dead a few days after birth. The chromosomal aberration was present in 100% of the plates examined.

Occasional chromosomal alterations, found in the patient's karyotype, might be held responsible of small phenotypic alterations. No alteration was found in the husband's karyotype.

A familial mosaicism involving chromosomes of group A. The father shows two clones: 46/normal and 47/trisomy A; the mother, 46/normal and 45/monosomy A. The two children are three clone mosaics: 45/monosomy A, 46/normal, 47/trisomy A.

Only one of the children is phenotypically abnormal: the other three members of the family have a normal appearance.

Relationship between karyotype and malformations is discussed. A tentative explanation is suggested.

The concepts of Chronon and Chronaxy of Gedda are discussed in the light of recent biochemical-genetic knowledge. It is proposed that the term «positive chronaxy» and «negative chronaxy» be employed to designate the period during which a gene is in active and inactive state, respectively. Other terms proposed are «recurrent positive chronaxy», «recurrent negative chronaxy» and « uncoordinated chronaxy». It is pointed out that the different chronaxy states of genes may be subject to modification by certain agents. If a given agent is able to change a gene from a negative chronaxy state into positive chronaxy state, the gene toward this agent behaves as being in a «conditionally negative chronaxy state». In the same sense, we can speak also of a «conditionally positive chronaxy state» of a gene. It is proposed that mutations facilitating malignant transformation of cells can, theoretically, occur in both the active and inactive segments of the DNA. If active segments of the DNA are affected, i.e. those in positive chronaxy state, the effects of such mutations would be expressed immediately. If, however, genes in negative chronaxy state have similar mutations, their effect would be expressed only if these genes become activated by some agents, either physiological or unphysiological. Malignancies facilitated by hormonal inbalance may represent instances or mutated gene activation by physiological agents while tumors caused by carginogenic substances with a structure resembling steroid hormones could be examples of gene activation by unphysiological agents.

The authors have studied the frequency and nature of associated malformations in a series of 1000 patients with congenital heart disease. Etiological factors have been statistically analyzed, too.

It has been recently shown that the human requirement for exogenous ascorbic acid and the disease, scurvy, are the result of a typical genetic disease syndrome caused by a defect on the gene controlling the synthesis of the enzyme protein, L-gulonolactone oxidase. The lack of this active enzyme in the human liver prevents Man from producing his own ascorbic acid; a synthesis which is regularly carried out by nearly all other mammals. This genetic disease has been named, Hypoascorbemia. This new concept of the genetic etiology of scurvy gives a much broader outlook and opens perspectives which were lacking in the previous fifty year old nutritional or trace “vitamin C” hypothesis. “Correction” of this genetic defect in Man is now possible since the availability of ascorbic acid in large quantities. By “correction” is meant the long-term administration of ascorbic acid in the large amounts the human liver would be synthesizing had this genetic defect not occurred. The mammals have long used the increased liver biosynthesis of ascorbic acid, under stress, to maintain homeostasis. The genetic defect prevents Humans from utilizing this important mammalian biochemical protective mechanism. Supplying exogenous ascorbic acid at the proper high dosage for full “correction” is merely duplicating a normal mammalian reaction. The medical implications of the full “correction” of this genetic disease are discussed and speculations on the effects of “correction” in the rheumatoid diseases, cardiovascular conditions, strokes, cancer and the aging process are extrapolated from the meager data already in the medical literature. This paper is mainly a plea for more thought along the medical possibilities opened by this new concept and for more clinical tests based on the rationales derived from the genetic disease viewpoint.

Most of the cases of Amalric's pigmentary macular dystrophy associated with deafmutism seem to be due to a rubella or to another viral infection of the mother during pregnancy. This association can sometimes probably also be due to an infectious disease of the early childhood. Heredity seems to be a rather exceptional factor.

The fingerprints of 15 MZ and 15 DZ female twin pairs have been studied for methodological purposes. Zygosity has been ascertained both on account of similarity criteria (polysymptomatic method, etc.) and of concordance ones (blood groups). The data have been analyzed both qualitatively and quantitatively. The complexity of the qualitative analysis has required an apposite methodology and the use of a 1620 IBM computer.

Similarities — at the qualitative level — and concordances — at the quantitative one — appear to be significantly different respectively in MZ and DZ twin pairs.

No conclusions are drawn from the present results. The final work, based on 100 twin pairs (cf. Tab. 1.1) will possibly allow better understanding of some topics rapidly dealt with in this mainly methodological note.

A study of 6375 births from the records of two hospitals of Delhi reveals that the incidence of oral clefts is more or less constant in both males and females. Evidence indicates that plural births are more associated with the harelip, cleft palate and cleft lip, than single births. In the same way, there is a positive association between oral clefts and higher age groups of parents. For this fact it can be mentioned that the incidence of oral clefts is lower in lower birth ranks and higher in higher birth ranks, which is again indirectly influenced by the higher age group of parents.