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arXiv · 2507.13605

A mixture distribution approach for assessing genetic impact from twin study

Zonghui Hu·Pengfei Li·Dean Follmann·Jing Qin
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Abstract

This work was motivated by a twin study with the goal of assessing the genetic control of immune traits. We propose a mixture bivariate distribution to model twin data where the underlying order within a pair is unclear. Though estimation from mixture distribution is usually subject to low convergence rate, the combined likelihood, which is constructed over monozygotic and dizygotic twins combined, reaches root-n consistency and allows effective statistical inference on the genetic impact. The method is applicable to general unordered pairs.

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Zonghui Hu, Pengfei Li, Dean Follmann, Jing Qin. 2025-07-18. A mixture distribution approach for assessing genetic impact from twin study. https://doi.org/10.1002/sim.9367

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