The levels of ABO plasma agglutinins were studied in 47 MZ and 30 same-sex DZ pairs of twins having the same blood group. The degree of genetic determination of this characteristic, as ascertained by the comparison of average titers and titration scores, does not seem to be high; despite the fact that the correlation coefficients were always lower among DZ, the F ratio was significant in relation to the anti-B of A persons only. The presence of these antibodies was also investigated in the saliva of 30 MZ and 26 DZ pairs. Since about the same degree of discordance was observed among these two types of twins, the role of inheritance in the variability of this trait must be low.

Fifty MZ and 51 same-sex DZ twins were studied for ABH salivary secretions and the amount of these substances measured in those with the same A1A2BO blood groups. Using the classical, manual inhibition test we verified: (a) Levels for the H antigen in A2 and B persons similar to, but in O and A1 lower than those obtained in other places; (b) Low averages for the A and B substances; (c) Mean intrapair differences for A and H, which were the double in DZ as in MZ twins, the estimated degree of genetic determination being 0.86 and 0.69 respectively; in both cases the F-ratio was significant at the 0.01 level; (d) If one discrepant family is disregarded the correlation coefficient between O parents and DZ children for the H antigen (0.48) is of the order of magnitude expected under a simple additive model of polygenic inheritance.

Tests were also made using a fully automated method. The intraclass correlation coefficients thus obtained in MZ and DZ were similar to those reached using the data obtained with the classical technique. The degree of concordance arrived at by the two methods was only fair, but this may have been due to extraneous factors related to the way the samples were handled.

Primidone and its metabolites Phenobarbital and Phenylethylmalondiamide were tested in cultures of human lymphocytes on possible effects of inducing chromosome aberrations. The substances examined ranged from concentrations lower than the therapeutic serum level to 10-75 times this value, which differed with the various substances. Phenylethylmalondiamide shows, besides an increase of spiralization defects at higher concentrations, which was typical for all three substances, no reaction on the chromosome structure.

By using the Friedman-test a statistically significant difference (P < 5%) could be found between the average aberration rates of the controls and the cultures which had been treated with Primidone and Phenobarbital. The test according to Wilcoxon and Wilcox shows that there is a statistically significant (P < 5%) difference between the aberration rates of controls and the respectively treated cultures. The higher values for percentage of aberrant mitoses are caused by the increase of gaps and breaks. There was, however, no proof for a linear dependence of the percentage of aberrant mitoses on the increasing concentrations of the substances. The number of tetraploid mitoses, endoreduplications and hyperploid cells was within the normal range.

Since in these investigations the number of chromosome exchanges was not increased, it can certainly be said that Primidone and Phenobarbital are not highly mutagenic substances.

The acridine orange staining of metaphases previously treated with hot salt solutions, exhibits a differential banding pattern of the chromosomes. According to the physicochemical interpretation of the stained structures, the green and red fluorescent segments of the chromosomes should be considered as constituted respectively by double-stranded DNA and single-stranded DNA. The banding pattern is relatively consistent in different metaphases, although some occasional variations of the bands may be referred to the interference of chromosomal acid proteins. In general, the sequence of the bands is compatible with the picture of the reverse banding.

The population of Andhra Pradesh has been considered ideal for the study of inbreeding effects in view of its high incidence of consanguinity. Information for the present investigation was obtained from 1,091 consecutive hospital single births to study the genetic load in the newborn in terms of mortality and malformation as a consequence of inbreeding. The nature of consanguinity was examined and the frequency of uncle-niece marriages was found to be lower than in other parts of Andhra Pradesh. The mortality load in the newborn was found to be two lethal equivalents per individual, while the malformation load at birth was half the mortality load.

Taste blindness for PTC has been studied in (a) 416 leprosy patients and 424 healthy subjects, and (b) 261 filarial patients and 136 normal individuals of both sexes. A significant difference was found between leprosy patients and the healthy control group in the proportion of nontasters (χ2 = 4.096, for 1 DF, P〈0.05). No significant difference could be observed between the filariasis and the control group (χ2 = 0.605, for 1 DF, P〉0.30).

A study of the fingerprints of the Sayyads of Lucknow district, Uttar Pradesh, has given the following frequencies: whorls 40.87%, loops 56.33% and arches 2.80%. The mean pattern intensity is 13.81 ± 0.27, showing no significant differences with neither the upper nor the lower-caste Hindus of U.P., excepting the Purabia Chamar.

As for the ridge count, the Sayyads show a mean of 151.52 ± 3.62, which is highest as compared to Hindu populations of U.P. However, no significant differences are apparent between the Sayyads and Brahmins, Rajputs, and Ahirs. The Sayyads are found to differ significantly from the earlier Muslim sample reported by Singh (1961).

A comparison of the Sayyads with their coreligionists residing in the distant lands from India fails to reveal consistent dermatoglyphic affinities.

Sexual variation in fingerprint types and pattern size, as measured by total ridge counts, has been examined in a sample of 84 Australian aborigines and compared with other populations. As it generally happens in a population, total ridge counts have been found to be higher in males than females on account of (1) the males' higher frequency of whorls and lower frequency of loops, and (2) the males' larger whorl counts. The higher incidence of arches in females than males has also been found to play a role.

A family is described in which three siblings were affected by Robin's syndrome (micrognathia and glossoptosis with cleft palate) in its severe form. Two children died very early in life, the third is surviving after surgical management and appropriate nursing care. The children were born from a consanguineous marriage (their parents were first cousins). This pedigree is highly suggestive of an autosomal recessive kind of inheritance. Malformations of the extremities (hands and/or feet) were present in the probands as well as in two relatives of the paternal line.