The physical development of 20 premature same-sex twin pairs with dissimilar birth weight was observed, as compared to a control group of 17 pairs of premature same-sex twins born with similar weight.

The comparison showed that greater differences in development occur between twin siblings born with dissimilar weight. The twins poorly grown in utero were at a disadvantage mainly in body weight.

In the preschool or school age, twins poorly grown in utero twice as often had underheight. Underheight was found more frequently in boys.

The degree of intrauterine dystrophy does not seem to be of great importance to the further development. Neither was any relationship found between the physical development of the dystrophic twin and the degree of prematurity, as defined by fetal age and birth weight of the larger twin.

Our data show that oxytocic perfusion should be liberally given during twin pregnancy labor, since its use is correlated with lower fetal mortality, especially of the second premature twin. This therapy might act, namely, by reducing the number of second-twin abnormal presentations. In our series, the higher mortality rate associated with lengthening of time interval between both births could be attributed to second-twin abnormal presentations. However, mortality rate versus time interval in spontaneous twin deliveries warrants obstetrical management providing second-twin birth within 15 minutes.

A number of facts that cannot be interpreted in terms of nuclear genes would seem to be interpretable in terms of cytoplasmic heredity. The hereditary role of the mitochondria has already been demonstrated in molds. The role of the cytoplasm (matrilineal heredity) has also been shown in some phanerogams, and analogous facts have been noted in insects and molluscs. In amphibians, the influence of an alteration of the egg cortical cytoplasm has been shown to reappear in the following generations. This cortical cytoplasm includes the morphological plan of the organism with its bilateral symmetry: mirror imaging in monozygotic twins would only be an extension of bilateral symmetry. In Tatusia novemcincta the twins may be morphologically or chemically different, which may only be explained by an unequal subdivision of a heterogenic cytoplasm. Similar facts are observed in human twinning. Monozygotic twins are usually discordant with respect to congenital malformations (especially symmelia and anencephaly), which may only be interpreted in terms of unequal distribution of cytoplasmic properties.

A new entity which belongs to the neuronal ceroid-lipofuscinoses has been delineated. The essential ophthalmologic features were absence of the ERG and progressive tapetoretinal degeneration leading to blindness at the age of 2 years. Electroretinography and fluoresceinangiography are of major importance for the diagnosis. The primary site of the retinal lesion seems to be the receptors and the pigment epithelium.

The hemoglobin pattern of 18 inbred strains of mice was studied by starch-gel electrophoresis. In 7 strains (C57BL/10, C57BL/6, C57BR/cd, C57L, C58, SWR, and SEC/1Re) the electrophoretic pattern was found to be of single-band type: in the remaining 11 strains (AKR, DBA/1, DBA/2, CBA, C3H/He, C3HeB/Fe, Fl/1Re, RF, 129, A, and A/He), 6 components were constantly observed when the electrophoretic run was carried out for 20 hours. Hemoglobin from late C57BL/6 fetuses showed an electrophoretic pattern identical to that of the adult animal. Hemoglobin from AKR and DBA/2 late fetuses and newborns showed an electrophoretic pattern similar to that of the adult animal, but the slowest band was more intensely stained as compared with the corresponding band of the adult animal.

This study showed that biological handicap with many complications at birth was much more recognized in the second-born than in the first-born twins. One of the most prominent intrapair differences was, for example, the weight at birth. However, intrapair differences, which were observed also in other physical measurements, diminished gradually with age. Moreover, as for intellectual ability, which was represented by the scores of the entrance examination test or standard achievement test, no remarkable influences due to handicap of the second-born were identified. Thus, it was concluded that the biological handicap seen in the second-born twin at birth did not give any significant effect on later development.

Natulan (Procarbazine) is a methylhydrazine derivative which in animal experiments inhibits a series of transplantable tumours. The Walker carcinoma is markedly affected. Even well established Walker tumours disappear completely under Natulan treatment. Tumour tissue is replaced by fibrous tissue. Natulan does not act selectively on neoplastic tissue, it also depresses the growth of other rapidly proliferating tissues such as the bone marrow.

As regards the mechanism of action the following data are known: Natulan lowers the mitotic index by prolonging the interphase and hindering the cell from entering into mitosis. In Ehrlich ascites tumour cells chromatid breaks were observed. Natulan depolymerizes deoxyribonucleic acid (DNA) in vitro. In vivo the synthesis of DNA is inhibited. Furthermore alkylation of purine bases has been demonstrated. All these mechanisms may be responsible for the cytotoxic effect of methylhydrazine derivatives. Natulan does not possess cross-resistance towards other cytotoxic agents. This phenomenon is a further proof of its particular mechanism of action.

Type 1 diabetes mellitus (IDDM) results from a chronic process of autoimmune destruction of ß cells of the Langerhans islets. The presence of autoantibodies (ICA, GADA, anti-IA2, IAA) in serum preceds the clinical onset of the disease. Genetic predisposition for IDDM is connected with HLA, CTLA-4 and insulin gene region.

The aim of the study was the genetic and immunological analysis of a triplet. One of them developed Type 1 diabetes mellitus. We analysed HLA class II, CTLA-4 and insulin gene polymorphisms in the whole family. Besides, we investigated immunological status of three brothers.

All patients present identical genotype for VNTR loci: D1S80, D17S5 and Apo B, as well as for HLA-DRB1, — DQA1, — DQB1, CTLA-4 gene and all studied insulin gene polymorphisms. That proves their monozigosity. The triplet presents strong genetic predisposition for IDDM. The two patients without overt diabetes have increased levels of ICA, GADA, IA2 and IAA.

This study is based on pedigrees of 287 patients with Rheumatic Fever, which are compared with pedigrees of 300 controls: 11,7 per cent of all relatives in the first group had rheumatic fever, compared to 2,2 per cent of all relatives in the control group.

An hereditary predisposition to rheumatic fever is definitevely to be admitted.

This predisposition is due to the presence of a principal autosomal dominant gene with reduced penetrance and variable expressivity.

It seems to have no genetic relationship to the diathesis of allergic diseases and the diathesi of degenerative connective tissue disorders mesenchymotic diathesis.

Since the MNS blood group system does not exhaust the total degrees of freedom under the Wright's equilibrium law, it was felt that the peculiar problems facing the detection of F (the fixation coefficient of Wright's model) from ABO blood group data may not be totally relevant to the MNS system. To verify this, a short discussion on the detection of F from MNS blood group data is given here.

The genetic study of sterility, although rather complex, may be carried out, as far as the parents are concerned, on the basis of existing detection methods. A number of forms of individual sterility may be detected on the basis of the caryotype (ovarian and testicular dysgenesis, hermaphroditism), while a chromosomal pathologic phenotype is missing for others, and the corresponding genotypes must be detected through clinico-genealogical methods (pseudohermaphroditism, adrenogenital syndrome, Laurence-Moon-Bardet-Biedl syndrome, hereditary malformations). It is noted that the problem of immunitary incompatibility is not sufficiently clear. Examples are presented of others forms of sterility depending on a lethal load of the conceptus, for which consanguineous marriages may be held largely responsible. Cases of sterility may also be found in relation to mental diseases. The importance of eugenic counseling is stressed.

This study was performed to examine the main characteristics of the French Romulus twin population: zygosity, chorionicity, sex, term and birthweight. A sample of 104 pairs of twins was distinguished by zygosity, chorionicity and sex, and divided into concordant and discordant birthweight groups. Fifty-three % (n = 55) of the fetus pairs studied were born at “ideal term” (35-38 weeks), and 25% (n = 26) were delivered at “preterm” (28-34 weeks). The very preterm (< 28 weeks), and “postterm” (> 38 weeks) represented altogether 22% (n = 23) of the sample. Of the 104 twin pairs, 68% (n = 71) differ by less than 15% in birthweight, and 32% (n = 33) have a birthweight difference higher than 15%. In dizygotic (DZ) pairs females had more tendency to be in the discordant group (p = 0.01) while in monochorionic-monozygotic (MC-MZ) pairs males were more discordant (p = 0.07). We found a significant interaction between sex and zygosity type (p = 0.02). Males had a birthweight difference significantly weaker than that of females in dichorionic-monozygotic (DC-MZ) and DZ twins whereas it was higher than that of females in MC-MZ twins. There were no MZ twin pairs with DC placentation over than 15% birthweight difference. Log linear analysis demonstrated a three-way interaction (p < 0.05) between term type, zygosity type and hypotrophy. Our data indicate that in the group of twins born between 35 and 38 weeks' gestation the crucial question still remains unsettled on how term and birhweight are related to zygotism and/or chorionicity.

New researches have made it evident that besides the two normal Hb, the adult one (a) and the phoetal (f), there are other pathologic Hb: c, e, s, d, g, h, i.

These Hb, excepting the h, are present in the hetherozygote on every healthy person and in the homozygote, excepting the g Hb, determine chronic hemolitic anemia.

The f Hb, or a very similar Hb, is present in the Thalassemia minor and major, in some homozygote cases of abnormal Hb, in the interreaction between two different genes of these Hb, or between one of these genes with the one of Thalassemia.

We may retain that the genes a, c, s, d, e, g, i, form an allelomorphic series. The gene Th is not a part of this series.

Since in the homozygotes ss, cc (in absence of the gene a) the quantity of abnormal Hb does not always reach the same percentage, we may logically retain that the different quantity of abnormal Hb possessed by the s and c hetherozygotes depends from the different synthetic capacity of the genes of the two abnormal Hb. The appareance of f Hb may be the expression of a phenomenon of physiopatological compensation, which occurs when Hb a formation is prevented.

Twins have an important place in mythology and a sacred character appears to be attached to them since the most ancient times. In ancient Egypt, the royal placenta was worshipped, being considered as the Pharao's twin (a conception that is still alive among certain African populations), and actually everyone was considered to possess a spiritual twin, the Ka or astral body, through whom it was supposed to be possible to operate with magic rituals and hit enemies. Twin gods were worshipped by Babylonians and Assyrians (who even introduced them among astronomic constellations), and may be also found in the Persian and Veda religions. In the classic, Greco-Roman world, the examples of twin gods and heroes are innumerable: from the twin sons of Zeus, the Dioscuri, to the opposite-sexed twin gods Apollo and Diana, to Rome's founders, Romulus and Remus, etc. Since the most ancient times, a magic conception is connected to the twins, either in a positive or a negative sense, but often with some kind of a “fatidic” aspect. Such a two-faced approach to the phenomenon of twinning, that variously characterizes neareast, protomediterranean, classic, and other ancient civilizations, may still be found in contemporary primitive societies.

Fifteen hundred palmar prints of normal persons and patients suffering from various diseases were studied and classified as to dermal ridge configurations at the base of digit IV, after the exclusion of main line C courses with endings at one of the palmar marginal regions. This classification scheme, based on the three classical reduction forms of line C (O,X(8),x), resulted in the differentiation of three main groups, A, B, and C. Within these main groups, pattern types with strong similarity were combined to subgroups allowing an easier documentation. Twin and family data were used to test whether the described pattern types, besides the classical abortive states O,X and x of line C (called special and intermediate forms), are heritable and for which of them a remarkable reduction tendency could be established. The results allow us to confirm the main grouping and the assumed reduction tendency of the special forms of group A.

The perinatal mortality rate in multiple pregnancies has been examined both in literature data (where it reaches an average value of 17.5%), and on a sample of 619 twin deliveries from the Danzig population.

Adenosine deaminase (ADA) isoenzymes in a Swedish population of 342 unrelated individuals have been determined according to the method of Spencer et al. (1968). The gene frequencies found were 0.9357 and 0.0643 for ADA 1 and ADA 2 respectively. These frequencies are in good accordance with previous investigations.

A chromosomal study has been carried out on 11 patients with otosclerosis. All caryotypes were invariably normal. Those group-D chromosomal anomalies of structure and number reported in the literature could therefore not be confirmed.