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Emma Kowal and colleagues argue against restricting access to genomic data collected from indigenous peoples (Nature 546, 474; 2017), citing our study of Aboriginal Australians as a case in point (A.-S. Malaspinas et al. Nature 538, 207–214; 2016). In fact, the collection of these samples was fully in accordance with Australia's National Statement on Ethical Conduct in Human Research. Moreover, the researchers worked with the Aboriginal donors to develop the conditions for data sharing.

Supported gold nanoparticles have excited much interest owing to their unusual and somewhat unexpected catalytic properties, but the origin of the catalytic activity is still not fully understood. Experimental work on gold particles supported on a titanium dioxide (110) single-crystal surface has established a striking size threshold effect associated with a metal-to-insulator transition, with gold particles catalytically active only if their diameters fall below approximately 3.5 nm. However, the remarkable catalytic behaviour might also in part arise from strong electronic interaction between the gold and the titanium dioxide support. In the case of industrially important selective oxidation reactions, explanation of the effectiveness of gold nanoparticle catalysts is complicated by the need for additives to drive the reaction, and/or the presence of strong support interactions and incomplete understanding of their possible catalytic role. Here we show that very small gold entities ( approximately 1.4 nm) derived from 55-atom gold clusters and supported on inert materials are efficient and robust catalysts for the selective oxidation of styrene by dioxygen. We find a sharp size threshold in catalytic activity, in that particles with diameters of approximately 2 nm and above are completely inactive. Our observations suggest that catalytic activity arises from the altered electronic structure intrinsic to small gold nanoparticles, and that the use of 55-atom gold clusters may prove a viable route to the synthesis of robust gold catalysts suited to practical application.

The sequencing of a complete horse genome from a bone dating to around 700,000 years ago sheds light on equine evolution and dramatically extends the known limit of DNA survival. See Letter p.74 A low-coverage draft genome sequence has been obtained from a horse bone recovered from a permafrost site in the Yukon Territory, Canada, dated to around 560,000–780,000 years before present. This is by far the earliest genome sequence so far determined. The data were compared to draft genome sequences for a Late Pleistocene horse, those of five contemporary domestic horse breeds, a Przewalski's horse and a donkey. Comparative genomics suggest that the Equus lineage that gave rise to all contemporary horses, zebras and donkeys originated about 4.0–4.5 million years ago — much earlier than previously suspected. The data support the contention that Przewalski's horses — an endangered subspecies native to the Mongolian steppes — represent the last surviving wild horse population.

Ancient DNA studies have typically used multi-copy mitochondrial DNA sequences1,2. This is largely because single-locus nuclear genes have been difficult to recover from sub-fossil material3, restricting the scope of ancient DNA research. Here, we have isolated single-locus nuclear DNA markers to assign the sex of 115 extinct moa and, in combination with a mitochondrial DNA phylogeny, tested competing hypotheses about the specific status of moa taxa. Moa were large ratite birds that showed extreme size variation both within and among species4. For some taxa, this large variation was hypothesized to represent sexual dimorphism, while for others it was argued to reflect the existence of different species5. Our results show that moa were characterized by extreme reverse sexual dimorphism and as a result we have been able to clarify the number of moa species. For example, we show that the three recognized ‘species’ of Dinornis comprised only two monophyletic groups and that two of these ‘species’ comprised individuals of one sex only. This study also illustrates that single-locus nuclear DNA sequences can be consistently recovered from ancient material.

DNA is particularly well preserved in hair — enabling the genome of a human to be sequenced, and his ancestry and appearance to be determined, from 4,000-year-old remains.

A PRINCIPAL objective in the study of heterogeneous catalysis is the determination of the structure and composition of solid surfaces under reaction conditions. Most applicable spectroscopic methods achieve surface sensitivity by detecting ejected electrons which have very short mean free paths in the solid1. But such measurements must be carried out in vacuum, whereas catalytic reactions are typically carried out at pressures of at least one atmosphere. Although such a gas environment can be penetrated by X-rays or neutrons, these probe the bulk properties of solids rather than their surface properties2–6. Here, we describe how a catalyst sample and its gas environment may be configured so as to constitute a photocathode ionization detector7. By monitoring the ionization cascade rather than photon absorption, we show that X-ray absorption spectroscopy can be used to examine monolayer amounts of adsorbate on the surface of a practical catalyst at one atmosphere pressure. The wider application of this technique to complex systems in a variety of environments has considerable potential for the study of heterogeneous catalysis, and may be extended to other areas of interfacial science.

The existence of cannibalism is one of the most controversial issues in the archaeology of the American Southwest. Disarticulated, cut-marked and heat-altered human remains from non-burial contexts at prehistoric Puebloan (Anasazi) archaeological sites in the Four Corners region of the American Southwest have been interpreted by some scholars as evidence of cannibalism. Osteological studies indicate that many of the disarticulated bodies found at these sites were processed in a manner consistent with food preparation. Opponents of this interpretation point out that non-cannibalistic practices such as secondary interment, corpse mutilation and ritualized witch executions might account for the assemblages. Osteological evidence alone does not document the actual ingestion of human flesh. Here we show consumption of human flesh did occur as demonstrated in preserved human waste containing identifiable human tissue remains from a site with osteological evidence of cannibalism.

The gag and pol genes of the human immunodeficiency virus type 1 (HIV-1) (ref. 1) are translated as two polyproteins, Pr55gag and Pr160gag-pol (refs 2-6), which are subsequently cleaved by the action of a virus-encoded protease into the four structural gag proteins of the virion core (p17, p24, p7 and p6) and the pol-encoded enzymes essential for retrovirus replication (protease, reverse transcriptase, ribonuclease H, and endonuclease). Mutational inactivation of the proteases of HIV-1 and other retroviruses results in immature, non-infectious virions, indicating that exogenous inhibition of the protease may represent an attractive approach to anti-AIDS therapy. Here we demonstrate that synthetic peptide analogues, which are potent inhibitors of purified HIV-1 protease, inhibit the processing of the viral polyproteins in cultures of HIV-1-infected T lymphocytes and attenuate viral infectivity.

The reality of a complete Neanderthal genome draws near, as two papers report the sequencing of large amounts of Neanderthal DNA. The results will help to answer some central questions on human evolution.

Multiple choice experiments using 29 populations of Drosophila melanogaster from around the world were performed to measure any divergence in the mating system of this species. Courting flies were observed in a total of 691 mating experiments and 9,280 copulations. Only two of the 38 interpopulation crosses exhibited a significant divergence from random mating. However, neither of these represent a trend towards positive assortative mating. This suggests that there is considerable stability in the mate recognition system of D. melanogaster in spite of the substantial genetical and morphological differentiation which exists throughout the cosmopolitan distribution of this species.

Duchenne muscular dystrophy (DMD) is an X-linked recessive genetic disorder for which the biochemical defect is as yet unknown. Recently, two cloned segments of human X-chromosome DNA have been described which detect structural alterations within or near the genetic locus responsible for the disorder. Both of these cloned segments were described as tightly linked to the locus and were capable of detecting deletions in the DNA of boys affected with DMD. In an attempt to determine more precisely the occurrence of these deletions within a large population of DMD patients and the accuracy of one of the segments, DXS164 (pERT87), in determining the inheritance of the DMD X chromosome, the subclones 1, 8 and 15 were made available to many investigators throughout the world. Here we describe the combined results of more than 20 research laboratories with respect to the occurrence of deletions at the DXS164 locus in DNA samples isolated from patients with DMD and Becker muscular dystrophy (BMD). The results indicate that the DXS164 locus apparently recombines with DMD 5% of the time, but is probably located between independent sites of mutation which yield DMD. The breakpoints of some deletions are delineated within the DXS164 locus, and it is evident that the deletions at the DMD locus are frequent and extremely large.

The population history of Aboriginal Australians remains largely uncharacterised, not least because of a lack of extensive genomic data. We generated high-coverage genomes for 83 geographically diverse Aboriginal Australians (all speakers of Pama-Nyungan languages) and 25 Papuans from the New Guinea Highlands. We find that Papuan and Aboriginal Australian ancestors diversified from each other 25-40 thousand years ago (kya), suggesting early population structure in the ancient continent of Sahul (Australia, New Guinea and Tasmania). However, all contemporary Aboriginal Australians studied descend from a single founding population that differentiated around 10-32 kya. We infer a population expansion in northeast Australia during the Holocene (past c.10 kya) associated with limited gene flow from this region to the rest of Australia. This is broadly consistent with the spread of the Pama-Nyungan languages and cultural changes taking place across the continent in the mid-Holocene. We estimate that Aboriginal Australians and Papuans diverged from Eurasians 60-100 kya, following a single out of Africa dispersal and subsequent admixture with different archaic populations. Finally, we report evidence of selection in Aboriginal Australians potentially associated with living in the desert.

IN 1961 we reported the results of studies on a case of acute, iso-immune haemolytic anaemia experimentally induced in a CwDe/Ce(R1wR1) volunteer transfused with plasma containing exceptional anti-CD antibodies1. Antibody sensitization of the recipient's erythrocytes was detected by the direct antiglobulin test (Coombs) up to day 133 following the plasma transfusion. Positive tests for antibody-coated red cells were obtained in the serum + albumin (a mixture of equal parts of human serum and 30 per cent bovine albumin) slide sensitization test through the 98th post-transfusion day. The study of the recipient's post-transfusion serum specimens for free, circulating antibodies in titration procedures employing serum + albumin revealed three distinct periods of antibody activity especially with the cDe/ce(R0R0) primary test cells. The first of these appearing between the first hour and the ninth post-transfusion day was interpreted as surplus antibodies remaining from those transfused in the anti-CD plasma, the second between post-transfusion days 14 and 98 as indicative of eluted or released antibodies and the final between days 105 and 140 as possible auto-immune antibodies representing the product of active immunization by the recipient himself. The peak titres of the free, circulating antibodies in the second and third periods of increased antibody activity were definitely higher than those obtained in the first, immediate post-transfusion one. In view of the Rh genotype of the recipient (CwDe/Ce), the serologic specificity of the transfused antibodies (anti-CD) and the observation that the antibodies in the third peak were reactive against the C and D antigens in the Rh system, no conclusive proof of the auto-antibody nature of these antibodies could be established on the basis of blood group specificity.

THE presence of the Dia blood group antigen among various Indian tribes native to South and Central America has been well established, the incidence ranging from 3.7 to 45.8 per cent. Rare exceptions are the two documented groups where no Di(a+) examples have been demonstrated1,2. In North American Indians it has been found in 10.8 per cent of Chippewas of northern Minnesota3, 8.6 per cent of Crees of northern Manitoba4, 6.0 per cent of Bloods of southern Alberta5, 0.35 per cent of Athabascans of Alaska6, 5.6 per cent of Penobscots of Maine7 and 0.00 per cent of Cherokees of Oklahoma8.

THE presence of C-6 oxygenated steroids in neonatal urine was first reported by Ulstrom et al.1. It has been demonstrated2,3 that placental tissue incubated under standard conditions, is able to oxygenate at the C-6 position, while the work of Frantz et al.4 has indicated that during pregnancy the urinary concentrations of the polar steroid 6β-hydroxycortisol is elevated above the normal non-pregnant state. It appeared likely, therefore, that similar polar steroids might be present in liquor amnii.

A METHOD of subdividing an associated population the individuals of which are specified by the presence or absence of a number of attributes has been described previously1; the process is ultimately derived from the R-techniques of factor analysis, and the groups of individuals so obtained will be called R-groups. The attributes may similarly be subdivided into Q-groups by the corresponding Q-techniques. There results a 2-way table in which every attribute-individual record is referred to one of each kind of group. The requirement is to extract from this table the most concentrated groups of records, the attribute-individual noda around which the population may be regarded as varying. The problem is essentially that of establishing coincidences between R and Q factors; even in normal factor analysis the coincidences are impaired in the formation of the correlation matrix2,3, and in a subdivision process involving successive correlation matrices the divergence may well be considerable.

THE blood group antigen Mia was discovered by Levine, Stock, Kuhmichel and Bronikovsky1 in 1951. Anti-Mia, the antibody necessary for the identification of the antigen, was made by a mother in response to immunization by her Mi(a +) fœtus which, as a result, had severe haemolytic disease. The antigen was shown to be inherited as a dominant character. The antigen was evidently rare, for no example was found in testing 425 random people.