Transmission of polycystic ovary syndrome susceptibility single-nucleotide polymorphisms and their association with phenotype changes in offspring

STUDY QUESTION: Does the inheritance of polycystic ovary syndrome (PCOS) susceptibility single-nucleotide polymorphism affect the phenotype of offspring? SUMMARY ANSWER: Male offspring who inherit PCOS-related genetic variations from PCOS mothers were more susceptible to developing the metabolic abnormality in their later life. WHAT IS KNOWN ALREADY: Genetic factors are considered the major etiology of PCOS. Previous studies have highlighted that offspring of women with PCOS had an increased risk of the same disease or PCOS-like symptoms. STUDY DESIGN, SIZE, DURATION: The study involved 172 children born to women with PCOS and 529 children born to non-PCOS women. All offspring were conceived by assisted reproductive technologies. PARTICIPANTS/MATERIALS, SETTING, METHODS: The offspring ranged from 1 to 8 years old. Metabolic phenotype analyses were performed in offspring aged from 2 to 8 (N = 619). Sanger sequencing, TaqMan and Sequenom MassARRAY were used to sequence the samples. MAIN RESULTS AND THE ROLE OF CHANCE: In male offspring, the fasting insulin (FINS) (P = 0.037) homeostasis model assessment of insulin resistance (HOMA-IR) (P = 0.038) and the homeostasis model assessment of pancreatic beta-cell function (HOMA-beta) (P = 0.038) levels were higher in offspring of PCOS mothers compared to controls. In female offspring, PCOS offspring had a significantly higher anti-Mullerian hormone levels (P = 0.001) compared to those from control mothers. In male offspring of PCOS mothers, subjects with a T allele at rs2349415 in the gene FSHR had higher FINS (P = 0.023), HOMA-IR (P = 0.030) and HOMA-beta levels (P = 0.013) than those in the homozygous CC group. The same increased trend in FINS, HOMA-IR and HOMA-beta levels could be found in the CC and TC group in rs2268361 located in gene FSHR compared to the TT group (P = 0.029, P = 0.030, P = 0.046, respectively). As for rs10818854 in the DENND1A gene, the AA and AG group had a higher FINS (P = 0.037) and HOMA-beta (P = 0.008) levels than the homozygous CC group. LIMITATIONS, REASONS FOR CAUTION: Firstly, the offspring may be too young to see any phenotype changes. Secondly, this study only analyzed the differences of genotype frequency using the dominant model instead of all three models due to the limited sample size of the homozygous model. The results, therefore, should be replicated and performed in a larger sample size population. Thirdly, environmental impacts cannot be ruled out. WIDER IMPLICATIONS OF THE FINDINGS: The findings presented in this thesis add to our understanding the changes in offspring born to PCOS women and remind us to consider early intervention to avoid more severe effects.