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This article examines the socioeconomic and demographic correlates that are associated with whether biracial children with an Asian parent are racially identified with their Asian parent or with their non-Asian parent. With data extracted from the 5-percent Public Use Microdata Sample (PUMS) of the 1990 census, we take into account explanatory variables at three levels: the child's characteristics, the parents' characteristics, and the locale's racial composition. Our results indicate that the racial identification of biracial children with an Asian parent is to a large extent an arbitrary option within today's prevailing racial classification scheme. We find empirical evidence in support of the theoretical proposition that both assimilation and awareness of Asian heritage affect the racial identification of biracial children with an Asian parent. [ABSTRACT FROM AUTHOR]

Aedes (Stegomyia) albopictus, also known as the Asian tiger mosquito, is a mosquito which originated in Asia. In recent years, it has become increasingly rampant throughout the world. This mosquito can transmit several arboviruses, including dengue, Zika and chikungunya viruses, and is considered a public health threat. Despite the urgent need of genome engineering to analyze specific gene functions, progress in genetical manipulation of Ae. albopictus has been slow due to a lack of efficient methods and genetic markers. In the present study, we established targeted disruptions in two genes, kynurenine hydroxylase (kh) and dopachrome conversion enzyme (yellow), to analyze the feasibility of generating visible phenotypes with genome editing by the clustered regularly interspaced short palindromic repeats (CRISPR) / CRISPR‐associated protein 9 (Cas9) system in Ae. albopictus. Following Cas9 single guide RNA ribonucleoprotein injection into the posterior end of pre‐blastoderm embryos, 30%–50% of fertile survivors produced alleles that failed to complement existing kh and yellow mutations. Complete eye and body pigmentation defects were readily observed in G1 pupae and adults, indicating successful generation of highly heritable mutations. We conclude that the CRISPR/Cas9‐mediated gene editing system can be used in Ae. albopictus and that it can be adopted as an efficient tool for genome‐scale analysis and biological study. [ABSTRACT FROM AUTHOR]

The brown planthopper (Nilaparvata lugens) is a major destructive rice pest in Asia. High levels of insecticide resistance have been frequently reported, and the G932C mutation in the chitin synthase 1 (CHS1) gene has been found to mediate buprofezin resistance. However, there has been no direct evidence to confirm the functional significance of the single G932C substitution mutation leading to buprofezin resistance in N. lugens. Here, we successfully constructed a knock-in homozygous strain (Nl-G932C) of N. lugens using CRISPR/Cas9 coupled with homology-directed repair (HDR). Compared with the background strain susceptible to buprofezin (Nl-SS), the knock-in strain (Nl-G932C) showed a 94.9-fold resistance to buprofezin. Furthermore, resistant strains (Nl-932C) isolated from the field exhibited a 2078.8-fold resistance to buprofezin, indicating that there are other mechanisms contributing to buprofezin resistance in the field. Inheritance analysis showed that the resistance trait is incomplete dominance. In addition, the Nl-G932C strain had a relative fitness of 0.33 with a substantially decreased survival rate, emergence rate, and fecundity. This study provided in vivo functional evidence for the causality of G932C substitution mutation of CHS1 with buprofezin resistance and valuable information for facilitating the development of resistance management strategies in N. lugens. This is the first example of using CRISPR/Cas9 gene-editing technology in a hemipteran insect to directly confirm the role of a candidate target site mutation in insecticide resistance. [Display omitted] • A knock-in strain (Nl-G932C) of Nilaparvata lugens was created using CRISPR/Cas9. • Nl-G932C showed a 94.9-fold resistance to buprofezin compared to susceptible strain. • Nl-G932C showed fitness disadvantage with low survivorship, emergence and fecundity. • The low fitness may help manage buprofezin resistance of N. lugens in the field. [ABSTRACT FROM AUTHOR]