Learning to make choices that yield rewarding outcomes requires the computation of three distinct signals: stimulus values that are used to guide choices at the time of decision making, experienced utility signals that are used to evaluate the outcomes of those decisions and prediction errors that are used to update the values assigned to stimuli during reward learning. Here we investigated whether monetary and social rewards involve overlapping neural substrates during these computations. Subjects engaged in two probabilistic reward learning tasks that were identical except that rewards were either social (pictures of smiling or angry people) or monetary (gaining or losing money). We found substantial overlap between the two types of rewards for all components of the learning process: a common area of ventromedial prefrontal cortex (vmPFC) correlated with stimulus value at the time of choice and another common area of vmPFC correlated with reward magnitude and common areas in the striatum correlated with prediction errors. Taken together, the findings support the hypothesis that shared anatomical substrates are involved in the computation of both monetary and social rewards.

The phylogenetic relationships of numerous branches within the core Y-chromosome haplogroup R-M207 support a West Asian origin of haplogroup R1b, its initial differentiation there followed by a rapid spread of one of its sub-clades carrying the M269 mutation to Europe. Here, we present phylogeographically resolved data for 2043 M269-derived Y-chromosomes from 118 West Asian and European populations assessed for the M412 SNP that largely separates the majority of Central and West European R1b lineages from those observed in Eastern Europe, the Circum-Uralic region, the Near East, the Caucasus and Pakistan. Within the M412 dichotomy, the major S116 sub-clade shows a frequency peak in the upper Danube basin and Paris area with declining frequency toward Italy, Iberia, Southern France and British Isles. Although this frequency pattern closely approximates the spread of the Linearbandkeramik (LBK), Neolithic culture, an advent leading to a number of pre-historic cultural developments during the past ≤10 thousand years, more complex pre-Neolithic scenarios remain possible for the L23(xM412) components in Southeast Europe and elsewhere.

Background

People with autism have abnormal preferences, ranging from an apparent lack of preference for social stimuli to unusually strong preferences for restricted sets of highly idiosyncratic stimuli. Yet the profile of preferences across social and nonsocial domains has not been mapped out in detail, and the processes responsible remain poorly understood.

Methods

To assess preferences across a range of stimuli, we measured real monetary donations to 50 charities spanning categories pertaining to people, mental health, animals, or the environment. We compared the donations made by 16 high-functioning adults with autism to those made by neurotypical controls matched on age, gender and education. We additionally collected ratings of how people evaluated the different charities.

Results

Compared with controls, high-functioning adults with autism donated less overall and also showed a significantly disproportionate reduction in donations to people charities compared with donations to the other charities. Furthermore, whereas controls discriminated strongly between different people charities, choosing to donate a lot of money to some and very little to others, much less discrimination was seen in the autism group. Ratings that probed how participants constructed their preferences did not differ between groups, except for a difference in the perceived impact of pictures and text information about people charities. Strikingly, there were some charities related to mental health, and autism in particular, to which the autism group donated considerably more than did the controls.

Conclusions

People with autism were found to have reduced preference and sensitivity towards charities benefiting other people. The findings provide evidence for a domain-specific impairment in social cognition in autism spectrum disorder, and in particular in linking otherwise intact social knowledge to the construction of value signals on which preferences regarding other people are based.

A leading hypothesis to explain the social dysfunction in people with autism spectrum disorders (ASD) is that they exhibit a deficit in reward processing and motivation specific to social stimuli. However, there have been few direct tests of this hypothesis to date. Here we used an instrumental reward learning task that contrasted learning with social rewards (pictures of positive and negative faces) against learning with monetary reward (winning and losing money). The two tasks were structurally identical except for the type of reward, permitting direct comparisons. We tested 10 high-functioning people with ASD (7M, 3F) and 10 healthy controls who were matched on gender, age, and education. We found no significant differences between the two groups in terms of overall ability behaviorally to discriminate positive from negative slot machines, reaction-times, and valence ratings, However, there was a specific impairment in the ASD group in learning to choose social rewards, compared to monetary rewards: they had a significantly lower cumulative number of choices of the most rewarding social slot machine, and had a significantly slower initial learning rate for the socially rewarding slot machine, compared to the controls. The findings show a deficit in reward learning in ASD that is greater for social rewards than for monetary rewards, and support the hypothesis of a disproportionate impairment in social reward processing in ASD.

NarL and NarP are paralogous response regulators that control anaerobic gene expression in response to the favoured electron acceptors nitrate and nitrite. Their DNA-binding carboxyl termini are in the widespread GerE–LuxR–FixJ subfamily of tetrahelical helix–turn–helix domains. Previous biochemical and crystallographic studies with NarL suggest that dimerization and DNA binding by the carboxyl-terminal domain (CTD) is inhibited by the unphosphorylated amino-terminal receiver domain. We report here that NarL-CTD and NarP-CTD, liberated from their receiver domains, activated transcription in vivo from the class II napF and yeaR operon control regions, but failed to activate from the class I narG and fdnG operon control regions. Alanine substitutions were made to examine requirements for residues in the NarL DNA recognition helix. Substitutions for Val-189 and Arg-192 blocked DNA binding as assayed both in vivo and in vitro, whereas substitution for Arg-188 had a strong effect only in vivo. Similar results were obtained with the corresponding residues in NarP. Finally, Ala substitutions identified residues within the NarL CTD as important for transcription activation. Overall, results are congruent with those obtained for other GerE-family members, including GerE, TraR, LuxR and FixJ.

Human Y-chromosome haplogroup structure is largely circumscribed by continental boundaries. One notable exception to this general pattern is the young haplogroup R1a that exhibits post-Glacial coalescent times and relates the paternal ancestry of more than 10% of men in a wide geographic area extending from South Asia to Central East Europe and South Siberia. Its origin and dispersal patterns are poorly understood as no marker has yet been described that would distinguish European R1a chromosomes from Asian. Here we present frequency and haplotype diversity estimates for more than 2000 R1a chromosomes assessed for several newly discovered SNP markers that introduce the onset of informative R1a subdivisions by geography. Marker M434 has a low frequency and a late origin in West Asia bearing witness to recent gene flow over the Arabian Sea. Conversely, marker M458 has a significant frequency in Europe, exceeding 30% in its core area in Eastern Europe and comprising up to 70% of all M17 chromosomes present there. The diversity and frequency profiles of M458 suggest its origin during the early Holocene and a subsequent expansion likely related to a number of prehistoric cultural developments in the region. Its primary frequency and diversity distribution correlates well with some of the major Central and East European river basins where settled farming was established before its spread further eastward. Importantly, the virtual absence of M458 chromosomes outside Europe speaks against substantial patrilineal gene flow from East Europe to Asia, including to India, at least since the mid-Holocene.

Background

The process of Greek colonization of the central and western Mediterranean during the Archaic and Classical Eras has been understudied from the perspective of population genetics. To investigate the Y chromosomal demography of Greek colonization in the western Mediterranean, Y-chromosome data consisting of 29 YSNPs and 37 YSTRs were compared from 51 subjects from Provence, 58 subjects from Smyrna and 31 subjects whose paternal ancestry derives from Asia Minor Phokaia, the ancestral embarkation port to the 6th century BCE Greek colonies of Massalia (Marseilles) and Alalie (Aleria, Corsica).

Results

19% of the Phokaian and 12% of the Smyrnian representatives were derived for haplogroup E-V13, characteristic of the Greek and Balkan mainland, while 4% of the Provencal, 4.6% of East Corsican and 1.6% of West Corsican samples were derived for E-V13. An admixture analysis estimated that 17% of the Y-chromosomes of Provence may be attributed to Greek colonization. Using the following putative Neolithic Anatolian lineages: J2a-DYS445 = 6, G2a-M406 and J2a1b1-M92, the data predict a 0% Neolithic contribution to Provence from Anatolia. Estimates of colonial Greek vs. indigenous Celto-Ligurian demography predict a maximum of a 10% Greek contribution, suggesting a Greek male elite-dominant input into the Iron Age Provence population.

Conclusions

Given the origin of viniculture in Provence is ascribed to Massalia, these results suggest that E-V13 may trace the demographic and socio-cultural impact of Greek colonization in Mediterranean Europe, a contribution that appears to be considerably larger than that of a Neolithic pioneer colonization.

Haplogroup J1 is a prevalent Y-chromosome lineage within the Near East. We report the frequency and YSTR diversity data for its major sub-clade (J1e). The overall expansion time estimated from 453 chromosomes is 10 000 years. Moreover, the previously described J1 (DYS388=13) chromosomes, frequently found in the Caucasus and eastern Anatolian populations, were ancestral to J1e and displayed an expansion time of 9000 years. For J1e, the Zagros/Taurus mountain region displays the highest haplotype diversity, although the J1e frequency increases toward the peripheral Arabian Peninsula. The southerly pattern of decreasing expansion time estimates is consistent with the serial drift and founder effect processes. The first such migration is predicted to have occurred at the onset of the Neolithic, and accordingly J1e parallels the establishment of rain-fed agriculture and semi-nomadic herders throughout the Fertile Crescent. Subsequently, J1e lineages might have been involved in episodes of the expansion of pastoralists into arid habitats coinciding with the spread of Arabic and other Semitic-speaking populations.

Aim

To determine the human Y-chromosome haplogroup backgrounds of intermediate-sized variant alleles displayed by short tandem repeat (STR) loci DYS392, DYS449, and DYS385, and to evaluate the potential of each intermediate variant to elucidate new phylogenetic substructure within the human Y-chromosome haplogroup tree.

Methods

Molecular characterization of lineages was achieved using a combination of Y-chromosome haplogroup defining binary polymorphisms and up to 37 short tandem repeat loci. DNA sequencing and median-joining network analyses were used to evaluate Y-chromosome lineages displaying intermediate variant alleles.

Results

We show that DYS392.2 occurs on a single haplogroup background, specifically I1*-M253, and likely represents a new phylogenetic subdivision in this European haplogroup. Intermediate variants DYS449.2 and DYS385.2 both occur on multiple haplogroup backgrounds, and when evaluated within specific haplogroup contexts, delineate new phylogenetic substructure, with DYS449.2 being informative within haplogroup A-P97 and DYS385.2 in haplogroups D-M145, E1b1a-M2, and R1b*-M343. Sequence analysis of variant alleles observed within the various haplogroup backgrounds showed that the nature of the intermediate variant differed, confirming the mutations arose independently.

Conclusions

Y-chromosome short tandem repeat intermediate variant alleles, while relatively rare, typically occur on multiple haplogroup backgrounds. This distribution indicates that such mutations arise at a rate generally intermediate to those of binary markers and Y-STR loci. As a result, intermediate-sized Y-STR variants can reveal phylogenetic substructure within the Y-chromosome phylogeny not currently detected by either binary or Y-STR markers alone, but only when such variants are evaluated within a haplogroup context.

Aim

To determine the human Y-chromosome haplogroup backgrounds of non-consensus DYS458.2 short tandem repeat alleles and evaluate their phylogenetic substructure and frequency in representative samples from the Middle East, Europe, and Pakistan.

Methods

Molecular characterization of lineages was achieved using a combination of Y-chromosome haplogroup defining binary polymorphisms and up to 37 short tandem repeat loci, including DYS388 to construct haplotypes. DNA sequencing of the DYS458 locus and median-joining network analyses were used to evaluate Y-chromosome lineages displaying the DYS458.2 motif.

Results

We showed that the DYS458.2 allelic innovation arose independently on at least two distinctive binary haplogroup backgrounds and possibly a third as well. The partial allele length pattern was fixed in all haplogroup J1 chromosomes examined, including its known rare sub-haplogroups. Within the alternative R1b3 associated M405 defined sub-haplogroup, both DYS458.0 and DYS458.2 allele classes occurred. A single chromosome also allocated to the R1b3-M269*(xM405) classification. The physical position of the partial insertion/deletion occurrence within the normal tetramer tract differed distinctly in each haplogroup context.

Conclusions

While unusual DYS458.2 alleles are informative, additional information for other linked polymorphic loci is required when using such non-conforming alleles to infer haplogroup background and common ancestry.