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Abstract All attempts to identify male-specific growth genes in humans have failed. This study aimed to clarify why men are taller than women. Microarray-based transcriptome analysis of the cartilage tissues of four adults and chondrocytes of 12 children showed that the median expression levels of SHOX, a growth gene in the pseudoautosomal region (PAR), were higher in male samples than in female samples. Male-dominant SHOX expression was confirmed by quantitative RT-PCR for 36 cartilage samples. Reduced representation bisulfite sequencing of four cartilage samples revealed sex-biased DNA methylation in the SHOX-flanking regions, and pyrosequencing of 22 cartilage samples confirmed male-dominant DNA methylation at the CpG sites in the SHOX upstream region and exon 6a. DNA methylation indexes of these regions were positively correlated with SHOX expression levels. These results, together with prior findings that PAR genes often exhibit male-dominant expression, imply that the relatively low SHOX expression in female cartilage tissues reflects the partial spread of X chromosome inactivation into PAR. Altogether, this study provides the first indication that sex differences in height are ascribed, at least in part, to the sex-dependent epigenetic regulation of SHOX. Our findings deserve further validation.

Abstract Preterm birth is known to be associated with chronic disease risk in adulthood whereby epigenetic memory may play a mechanistic role in disease susceptibility. Gestational age (GA) is the most important prognostic factor for preterm infants, and numerous DNA methylation alterations associated with GA have been revealed by epigenome-wide association studies. However, in human preterm infants, whether the methylation changes relate to transcription in the fetal state and persist after birth remains to be elucidated. Here, we identified 461 transcripts associated with GA (range 23–41 weeks) and 2093 candidate CpG sites for GA-involved epigenetic memory through analysis of methylome (110 cord blood and 47 postnatal blood) and transcriptional data (55 cord blood). Moreover, we discovered the trends of chromatin state, such as polycomb-binding, among these candidate sites. Fifty-four memory candidate sites showed correlation between methylation and transcription, and the representative corresponding gene was UCN, which encodes urocortin.

The present study examines second language (L2) acquisition of the Japanese reflexive zibun (self) by Chinese-speaking learners. The reflexive 'zibun' allows both local and long-distance (LD) binding interpretations. In a recent analysis, 'zibun' is categorized into three types: 'zibun' bound locally by a co-argument, 'zibun' bound by an empathic LD antecedent, and 'zibun' bound by a logophoric LD antecedent. An empathic antecedent is the participant in a sentence that the speaker most empathizes with, whereas, a logophoric antecedent is an individual “whose speech, thoughts, feelings, or general state of consciousness are reported” (Clements, 1975). Chinese also has a reflexive, 'ziji' (self), that can be bound by an LD antecedent, like Japanese 'zibun'. However, Chinese 'ziji' is categorized into two (not three) types: locally bound 'ziji' and 'ziji' bound by a logophoric LD antecedent (Huang, Li & Li, 2009). The goal of this study is to determine whether Chinese-speaking learners are able to distinguish the two different types of LD antecedent for 'zibun' in Japanese. Twenty-eight Chinese-speaking learners of Japanese at advanced levels of proficiency and 36 native speakers of Japanese participated in the study. The results showed that Chinese learners were unable to distinguish between the two types of LD antecedents, showing a persistent presence of first language (L1) transfer.