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Background: Generally, the translocation of SRY onto one of the X chromosomes leads to 46, XX testicular disorders of sex development, a relatively rare condition characterized by the presence of testicular tissue with a 46, XX karyotype. Three prenatal cases of unbalanced X; Y translocation carrying SRY were identified in this study. Methods: Structural variants were confirmed using single nucleotide polymorphism array and chromosomal karyotyping. X chromosome inactivation (XCI) was also analyzed. Detailed clinical features of the three cases were collected. Results: We identified two fetuses with maternal inherited unbalanced X; Y translocations carrying SRY and skewed XCI presenting with normal female external genitalia, and one fetus with de novo 46, XX (SRY+) and random XCI manifested male phenotypic external genitalia. Conclusion: This study reports that cases with unbalanced X; Y translocations carrying SRY manifested a normal female external genitalia in a prenatal setting. We speculate that the skewed XCI mediates the silence of SRY. In addition, our study emphasizes that combining clinical findings with pedigree analysis is critical for estimating the prognosis of fetuses with sex chromosome abnormalities. Key points: What's already known about this topic? Usually, unbalanced translocations of Y‐chromosomal fragments carrying SRY to the X chromosome or autosome lead to 46, XX or 45, X testicular disorders of sex development (DSD). What does this study add? 46, XX, SRY + individuals appeared normal female external genitalia with skewing X chromosome inactivation (XCI).Genotype‐phenotype correlation of chromosomal rearrangements in 46, XX, SRY + individuals is more variable and complex than previous reports. [ABSTRACT FROM AUTHOR]

Birth defects are an important factor for the quality of newborn population. With the development of molecular genetic technology, an increasing number of genetic disorders leading to birth defects can now be detected. The lack of the knowledge for the basics and clinical applications of molecular genetic techniques have emerged as a shortcoming for primary care physicians who have formed the first tier prevention for birth defects. Currently, government has paid more attention to the above problems and formulated more training programs for primary obstetricians and gynecologists, e.g., "Prenatal Screening and Prenatal Diagnosis Post Training Program", "National Birth Defects Training Program", "National Primary Obstetrician Training Program". To some extent, such programs have met the urgent need for birth defect prevention in primary hospitals. But at the same time, some problems have also emerged. For instance, the knowledge for birth defects among primary obstetricians and gynecologists is poor, and there is lack of young personnel. This article has aimed to discuss the strategies to systematically improve the ability for preventing birth defects among primary care physicians by analyzing the obstacles and challenges for primary obstetricians and gynecologists in the era of molecular genetic testing.