The incidences of 31 minor variants of the dental crown were scored from dental casts of samples taken from six European populations. Although several variants showed significant sex bias in one or other sample, only one (pits instead of furrow on premolar2) consistently favoured one sex. Associations between the variants were sought. Although few consistent associations were demonstrated, there was a possible tendency for extra cusps to occur together throughout the dentition. Distance statistics calculated between the samples were compatible with the expected genetical relationships of the samples, but only modern samples could be used since variants were destroyed by attrition in archeological samples. Before such distances can be considered reliable, it is necessary to know: (i)the extent to which environmental factors such as diet influence variant expression. (ii)whether or not variant bearing teeth are selectively destroyed by caries, which in civilised populations render a high proportion of most dentitions unscoreable.

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A 22-week fetus who had died in utero had a markedly hypoplastic nose and other facial abnormalities, short fingers, hypoplastic nails, and small phallus. Radiologically there was symmetrical cartilaginous stippling of the vertebral column, femoral heads, calcanei and elbows typical of chondrodysplasia punctata (CP), and metacarpal shortness and tiny pyramidal phalanges. The several causally different forms of CP are tabulated. Differential diagnosis suggests that the present case, which does not have limb shortness, could be a case of X-linked recessive brachytelephalangic chondrodysplasia punctata.

A de novo abnormal chromosome 15, with an inverted duplication of the segment (15q13.3 → 15q21.3) at 15q24.3, was found in a boy with mild developmental delay, facial dysmorphism, Marfan‐like appearance and severe language delay. There is an unusual disparity between the severe lack of speech and the presence of reasonable skills in other areas.

No abstract