Although genetic studies of allergic diseases have largely contributed to our understanding of disease pathogenesis, there is still a great potential for genetic studies of allergic diseases, and a better understanding of their genetic traits could advance the future diagnosis and treatment of allergic diseases. (i) Prediction of disease onset Genetic studies of allergic diseases are often questioned: are the genetic factors identified predictive of disease onset in individuals? To some extent, the clinical reference to family history of allergic diseases is itself a disguised application of genetic risk assessment. Moreover, clinical practice has demonstrated its reliability. However, we are not yet able to apply the rapidly accumulating results of genetic studies to clinical care, reflecting the complex interactions between genes and the environment that together cause disease and influence disease progression in individuals with typical disease phenotypes, and implying that the contribution of each genetic variant to predicting disease risk is small, with a relative risk of approximately 1.1 to 1.5 in individuals with typical genotypes. However, it is believed that as we study disease genetics more deeply, its effectiveness in predicting disease occurrence will increase and eventually be applied to clinical disease diagnosis. For example, a simulation study of 50 genes associated with disease incidence found that an area under the ROC curve (AUC) of 0.8 was achieved when the relative risk of genotype was 1.5 or the frequency of the risk allele was 10%, suggesting that the model is effective in predicting disease, but whether genetic testing can be used for future disease However, whether genetic testing can be used for future disease risk assessment and thus for prevention and diagnosis remains to be investigated in depth. A recent study on genetic factors on the risk of developing type II diabetes confirmed that genetic variation has very limited predictive power for disease. This shows the appropriateness of the excessive focus on the genetics of common complex diseases and the overestimation of the important role of genetics in complex diseases. However, we need to be optimistic that further identification of genetic risk factors for disease development and better models to analyze these factors will be important to improve the prediction of genetic factors in disease development and to explore new therapeutic strategies in the future. For example, in allergic diseases, it was recently found that FLG gene variants in children with eczema and food allergies had a 100% positive predictive value (PPV) for predicting later childhood allergic asthma. (ii) The monolithic view of predicting asthma subtypes for asthma or other allergic diseases focuses all attention on the Th2 response shift and activation of allergy-associated cells, such as mast cells, basophils and eosinophils. still requires the role of local genetic and environmental factors. In addition to this, treatment of allergic diseases with biologic agents targeting T-cell receptors such as CD25, IL-5, and TNF-a has shown good efficacy in only a limited number of patients, suggesting that these populations represent only a subset of the subtype groups in the allergic disease population. Therefore, the concept of defining phenotypic subtypes of asthma on the basis of differentiating gene-environment interactions is crucial and will also facilitate the guidance of personalized drug therapy in the future. (iii) Predicting disease severity Genetic studies of disease may also play an important role in predicting the severity of disease and predicting which populations have more severe disease onset, allowing for earlier interventions in clinical treatment. Many genetic diseases have been shown to be regulated by modifier genes rather than disease susceptibility genes. Despite the difficulty of exploring the complex interactions between susceptibility, environmental and therapeutic factors for modifier genes in allergic diseases such as asthma, many studies have identified modifier genes related to asthma severity. In the future, the discovery of these marker genes regarding disease severity could allow us to devote more medical resources to individuals who are at risk of developing severe disease, thereby reducing morbidity and mortality. (iv), personalized drug therapy Genetic pharmacology is a discipline that studies the influence of genetics on individualized differences in response to drug therapy and has received much attention in recent years. Genetic pharmacology studies in asthma patients have focused on bronchodilators, inhaled steroid hormones, and leukotriene modulators, which have shown that their genetic pharmacological effects may alter the expression and function of pharmacological targets and their metabolic systems due to single nucleotide polymorphisms, thereby affecting the efficacy of treatment for asthma. In view of this, the classification of these genetic pharmacological effects based on the characterization of candidate genes and at the genome-wide level would be beneficial for the personalized treatment of asthma as well as allergic diseases. Admittedly, the interpretation of genetic pharmacological effects and their clinical significance remains a very challenging issue at present.