Timasheva Yanina, Tuktarova Ilsiyar
Institute of Biochemistry and Genetics of Ufa Federal Research Centre of Russian Academy of Sciences, Ufa, Russia.
Department of Medical Genetics, Bashkir State Medical University, Ufa, Russia.
Forensic Sci Med Pathol. 2025 Jul 24. doi: 10.1007/s12024-025-01046-z.
Superfecundation, the fertilization of two oocytes by different spermatozoa within the same ovulatory cycle, can result in monopaternal or heteropaternal dizygotic twins. While monopaternal superfecundation is more common, heteropaternal superfecundation is rare and typically seen in disputed paternity cases. This study presents a case of heteropaternal superfecundation confirmed through forensic DNA analysis and reviews its occurrence in existing literature.
A forensic investigation was conducted in a court-ordered paternity case involving dizygotic twins, their mother, and an alleged father. Buccal swab samples were collected and analyzed using multiplex amplification of 19 STR markers and the amelogenin locus. A second DNA test confirmed the results. Additionally, a dataset of 2,679 paternity tests over 10 years was examined to estimate paternity exclusion rates in twin cases.
Genetic analysis confirmed the alleged father's paternity of twin 1 but not twin 2, with 14 out of 19 STR loci showing absent alleles in twin 2. The 10-year dataset showed 553 paternity exclusions (20.64% of cases), with 31 involving twins, of which one case (3.23%) was identified as heteropaternal superfecundation. No significant difference was found between paternity exclusion rates in twin and non-twin cases.
This case underscores the value of forensic genetic testing in detecting heteropaternal superfecundation, a rare occurrence with legal and social implications. Advances in DNA analysis may lead to more frequent identification of such cases.
同期复孕是指在同一个排卵周期内，两个不同的精子使两个卵母细胞受精，可导致单父系或异父系双卵双胞胎。虽然单父系同期复孕更为常见，但异父系同期复孕较为罕见，通常见于有争议的亲子鉴定案件。本研究报告了一例通过法医DNA分析确诊的异父系同期复孕病例，并回顾了现有文献中其发生情况。
在一项法院下令进行的涉及双卵双胞胎、其母亲和一名被指控父亲的亲子鉴定案件中，展开了法医调查。采集了口腔拭子样本，并使用19个STR标记和牙釉蛋白基因座的多重扩增进行分析。第二次DNA检测证实了结果。此外，检查了一个10年间2679例亲子鉴定的数据集，以估计双胞胎案件中的亲权排除率。
基因分析证实被指控父亲是双胞胎1的生父，但不是双胞胎2的生父，在19个STR基因座中，有14个在双胞胎2中显示等位基因缺失。10年的数据集显示有553例亲权排除（占案件的20.64%），其中31例涉及双胞胎，其中1例（3.23%）被确定为异父系同期复孕。双胞胎和亲权排除率在双胞胎和非双胞胎案件之间未发现显著差异。
本病例强调了法医基因检测在检测异父系同期复孕方面的价值，这是一种罕见情况，具有法律和社会意义。DNA分析的进展可能会导致更频繁地识别此类案件。
