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Objective To explore the association between obesity and precocious puberty from the perspective of genetic polymorphism. Design Two hundred and ninety‐eight pairs of girls in early puberty and age‐matched controls (±3 months) were recruited. The genotypes of four obesity‐related single‐nucleotide polymorphism (SNP) loci (rs10968576, rs12935153, rs4674340 and rs7635103) were determined and the effect of variation on early puberty in Chinese Han girls was evaluated. The unstimulated luteinizing hormone (LH), follicle‐stimulating hormone and estradiol levels were also measured to determine the relationship with SNP polymorphisms. Results The effect allele A of rs12935153 was associated with early puberty (odds ratio [OR] = 1.256, 95% confidence interval [CI]: 1.010–1.585), but the significance disappeared after multiple comparisons. After adjusting for body mass index, rs12935153 variation increased the risk of early puberty in additive (OR = 1.589, 95% CI: 1.222–2.066), dominant (OR = 1.788, 95% CI: 1.210–2.642) and recessive (OR = 1.915, 95% CI: 1.207–3.038) models of inheritance. Individuals harbouring AA genotype in rs12935153 had a risk of higher LH levels than that of wild type (OR = 1.668, 95% CI: 1.093–2.546). Conclusions The association between obesity and precocity can be explained from a genetic perspective. Our study suggests that variations in rs12935153 increase the risk of early puberty in Chinese girls. Further studies are needed to verify our findings.

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To solve the problem of poor weldability between TiAl-based and Ti2AlNb-based alloys, spark plasma diffusion bonding was employed to join a TiAl alloy and a Ti2AlNb alloy with a pure Ti foil as interlayer at 950 °C/10 KN/60 min. After welding, slow cooling was carried out at a rate of 5 °C/min, followed by homogenization at 800 °C for 24 h. The microstructural evolution and elemental migration of the joint were analyzed via a scanning electron microscope equipped with an energy dispersive spectrometer, while the mechanical properties of the joint were assessed via microhardness and tensile tests. The results show that the spark plasma diffusion bonding formed a joint of TiAl/Ti/Ti2AlNb without microcracks or microvoids, while also effectively protecting the base metal. Before heat treatment, the maximum hardness value (401 HV) appeared at the Ti2AlNb/Ti interface, while the minimum hardness value (281 HV) occurred in the TiAl base metal. The tensile strength of the heat-treated joint at room temperature was measured to be up to 454 MPa, with a brittle fracture occurring in the interlayer. The tensile strength of the joint at 650 °C was measured to be up to 538 MPa, with intergranular cracks occurring in the TiAl base metal.