To determine the small population as a specific group, several quantitative indexes have to be taken into consideration. The author, making use of these indexes, differentiates three types of small populations: the isolate, the « dem » and the « large dem ». The central type — the dem — is a group including 1,500 to 4,000 individuals with an increase of more than 20-25 per cent in 25 years (one generation); a high proportion, about 80 per cent, of the marriages is concluded inside the group and an insignificant part of the members have descended from allogenous ancestors. The inhabitants of a rural locality constitute in most cases a « dem ». Theoretical calculations as well as genealogical studies have shown that the preponderant part of adult members of a « dem » appear to be related to each other in the eighth degree (according to Tab. 2 - cousins thrice removed).

The syndrome of ataxia-telangiectasia was studied from a genetic standpoint on a material consisting of 7 original cases from four families, and of 31 cases from the literature. A cytogenetic analysis in one patient showed the normal diploid chromosome number, while the application of Brugger's test showed a random distribution of affected members in the investigated sibships. The observed frequency of affected individuals corresponds to the one to be expected, assuming a recessive monofactorial inheritance of the syndrome. Considering the small number of consanguineous marriages observed between parents of affected individuals, the conclusion can be drawn that ataxia-telangiectasia is not so rare a condition as it is generally assumed. The responsible gene shows a pleiotropic and lethal effect.

The frequency of twin births in Japan was calculated with the aid of the births statistics of the Japanese government for 1955-1961, and compared with the corresponding data in Western Germany. The results are follows:

1. The frequency of twin births in Japan is 0.64% of all births, while in Germany it is of 1.15%. The ratio of MZ to DZ twins is 63%: 37% in Japan and 32%: 68% in Germany.

2. The present results are mainly in agreement with two previous reports by Komai (1936) and Inouye (1956).

3. The frequency of MZ twin births in Japan is almost the same as in Germany, while the frequency of DZ twin births in Germany is about three times higher than in Japan. This study confirms the hypothesis that the difference of the frequency of twin births between Japan and Germany is only due to the difference of the frequency of DZ twin births.

The Authors have observed a high rate of chromosomal morphologic alterations in leukocyte cultures in 10 children who had previously undergone Roentgen irradiation for diagnostic purposes. Temporary alterations have been observed, such as interruptions of chromatine on the proteic thread, defined as achromatic lesions of one or more chromatids; fragmentations of chromatids; fragments without centromere; deletions; ring-chromosomes; dicentric and tricentric chromosomes and, in certain cases, increase of polyploid mitoses, both on account of endo-reduplications or of a lacking cytoplasm division.

Hereditary factors involved in the determination of the size, relative position and type of pattern formed by the dermal ridges in the interdigital areas of the palm have been investigated by means of twin and family studies. The sample consisted of 566 individuals of European descent. The ridge-counts of patterns in the interdigital areas were determined. Correction factors were introduced to compensate for different average counts in each interdigital area. The correlation coefficients between family relatives were calculated using the ridge-counts. The coefficient for monozygotic twins was .88±.04 and for parent and child from .346 to .425 and for sib pairs from .328 to .412. There was no evidence of sex-linkage or of the effects of dominance. Variation appeared to be determined by additive genes but an appreciable amount of variation of non-genetic origin was observed. Bilateral asymmetry in the ridge-count, type of pattern and relative position of the patterns was evident. Concordance rates in twins and other family members and pedigree data provided further evidence of hereditary influence in the determination of the position and type of pattern in the interdigital areas.

Cytogenetic studies were performed in six clinically typical cases of Turner's syndrome. In five of them an XO chromosome complement was observed. In the sixth case the chromosome number appeared normal, but karyotype analysis revealed the presence of three large metacentric chromosomes similar to No. 3. A diagnosis of presumptive isochromosome for the long arm of X was suggested by the autoradiographic evidence of late replication and by the presence of larger than normal Barr bodies and drumsticks.

Among 2,005 Swedish men the percentage of “non-tasters” for PTC is 18.4 ± 0.9 and by 1,051 women 12.8 ± 1.0. The difference is 5.6 ± 1.4%. The difference of “non-tasters” between women who are nulliparae (437) and others (614) is 19.5 — 8.1 = 11.4 ± 2.2%.

The karyotype has been analysed of two subjects with mandibulofacial dysostosis (Franceschetti's syndrome), considering that the main anomalies of this condition are also present in other malformations for which the association with particular genomic or chromosomal aberrations has been demonstrated.

In both subjects, the karyotype was normal.

The comparison of the clinical and cytogenetic data of this malformation with those of others (trisomy-D1 syndrome, trisomy-18 syndrome, deletion-18 syndrome) provides further evidence of the complexity of the genie systems controlling the processes of individuation during embryonic development, and of their interferences. However, this also shows how difficult it is to obtain human chromosome maps through the study of the macroscopic phenotypic characteristics of certain chromosomal anomalies.

A man of 32 is described suffering from a combination of three disorders: cutis verticis gyrata, severe mental deficiency and aplasia of the thyroid. Four of his close relatives were also severely retarded. The possibility is discussed of the syndrome being inherited through an X-linked recessive gene.

1. The author has worked-out a new system of finger-prints analysis through bringing together the types of pattern of the various fingers to a total qualitative value of the following 5 types: A-pattern 2.3%, AL-pattern 3.5%, L-pattern 61.8%, LW-pattern 21.4%, W-pattern 11.0%.

2. Calculations of frequency have shown that sex difference does not exist with respect to the various types of total qualitative value.

3. Mother/child calculations of correlation in tetrachoric tables have given the following results:

a) L/W: χ2 = 34.38; r = 0.46 ± 0.06;

b) A, AL, L/LW, W: χ2 = 27.38; r = 0.31 ± 0.05;

c) L/LW: χ2 = 3.75; r = 0.13 ± 0.07.

The author's purpose is to establish if there exists a propensity between fathers and sons about the papillar figures which are on the apical palanx of the fingers of the hand.

He has examined a sample of 31 families, each of them composed of a father and a number of sons, which generally varied from group to group, one to four, for a total of 76 sons.

After having carefully considered the possible statistical techniques to be employed in the research, the author has concluded that the most satisfactory method is a test directly ensuing from the mathching theory.

The application of the test revealed that for the two middle fingers, the index and the left annular, such a propensity between fathers and sons can be certainly estimated as existing; as to the right annular, the conclusion is doubtful; for the remaining fingers, the propensity is not admissible.

The author has systematized the hallucal dermatoglyphics in accordance with the pattern direction in whorl, longitudinal, transverse, and open-field patterns Neither sex difference nor any difference between the right/left foot could be demonstrated. A correlation with χ2-distribution mother/child gave for:

1. longitudinal/transverse pattern χ2=49.0;

2. longitudinal/whorl pattern χ2=12.3;

3. transverse/whorl pattern χ2=6.3.

The new quantitative evaluation of palmar dermatoglyphics is a radical modification of the metric method already proposed by the A. (1961). The change makes it extremely simple to apply, and it is not at all liable to varying interpretations from one scientist to another. This modification consists in plotting the circumference passing through the three nonaligned points represented by the triradii a, b, d (c has been intentionally excluded, for it is often absent or merely rudimentary). The end of each main line may thus be expressed by the angle at the centre measured (in an anti-clockwise direction for right hands and vice versa for left hands) from the triradius a to the point of intersection between the main line under study and the circumference plotted as described.

The coefficient r of correlation has been calculated in parent-parent, father-child, mother-child and sib-sib pairs, for the ends of line A and for those of line D expressed as above, and also for a number of other metric features resulting from the construction of the circumference. Very small nonsignificant values of r have been found in the case of the parent-parent pairs; in the other cases, on the contrary, the r values were as a rule statistically significant, showing the heritability of the features in question.

Differential trends of R/L Symmetry as shown by the incidences of Symmetry (S) and Asymmetry (A) in Cummins' summational Main Line Index, as based on the Burman material (400 ♂ & 71 ♀) are slightly higher in females than in males. However, these are not statistically significant.

By grouping MLI values in two categories, (a)-5 or 〈 5 and (b)-6 or 〉 6, it is found that MLI values above 6 are largely involved (relative to 5 or 〈 5) in contributing to the incidence of asymmetric R/L combinations of MLI. Further, the male-female differences in the three combinations (a) & (a), (a) & (b), (b) & (b) are statistically significant.

Cytological studies have shown that Down's syndrome (“ mongolism ”) is the result of a chromosomal anomaly which occurs either in one of the parent's germ cells or at a very early stage in (embryonic) development of the affected individual. The chromosomal anomaly involves the occurrence of a third number 21 chromosome, in addition to the normal complement of two, either separately (i. e., trisomy-21) or attached to one of the other acrocentric chromosomes (i. e., translocation to one of the chromosomes numbered 13-15 or 22 — Denver Report, 1960). Epidemiological studies have indicated that numerous factors are related to, and may affect, incidence of the chromosomal anomalies resulting in Down's syndrome. Studies by Collmann and Stoller (1962a, b) imply fluctuations of annual incidence with a 5-6 year periodicity, a higher incidence in urban compared to rural areas and a clusteting of affected births in certain geographic regions. Collmann and Stoller postulated an “ infectious agent, probably a virus ”, to account for their data. No connection, however, can yet be drawn between such a hypothesis and the established cytogenetic anomaly. Periodic fluctuations in incidence, which are characteristic of recurrent epidemics (Gordon, 1962), have also been reported for congenital anomalies other than Down's syndrome, such as anencephaly, spina bifida, and hydrocephaly (Collmann and Stoller, 1962b; Guthkelch, 1962; Alter, 1962; Slater, Watson and McDonald, 1964).

1. Data relating to hypertrichosis of the ear rim, lobe, tragus and antitragus in the Pahira are presented.

2. It has been indicated that (a) hypertrichosis of the rim is associated with that of the lobe, tragus and antitragus, and both may be controlled by the same genotype; (b) it may not be a characteristic of the Mediterranean race alone; and (c) its use as an “anthropological marker” is of limited value.

Both palm prints of 75 ♂ and 73 ♀ unrelated Maharashtrian students aged 8-18 have been collected and analysed according to Cummins & Midlo's methodology. The results are tabulated and discussed.

They concern the principal main line formulae and their terminations at Lines D, C, B, A; the distribution of the axial triradius, as well as the frequencies of whorls, loops, arches, vestiges and open-fields in the hypothenar, thenar and in the interdigital areas.

603 patients suffering from filariasis have been studied for A1A2BO blood groups; 281 for Duffy, Kell and rhesus blood groups; 178 for secretor factor; and 503 for MN blood groups, to find out if there is any association between filariasis and these blood groups. No association, whatsoever, has been found between the blood groups studied and filariasis.