Novel Bi-Allelic Variants of FANCM Cause Sertoli Cell-Only Syndrome and Non-Obstructive Azoospermia

Non-obstructive azoospermia (NOA) is the most severe disease in male infertility, but the genetic causes for the majority of NOA remain unknown. FANCM is a member of Fanconi Anemia (FA) core complex, whose defects are associated with cell hypersensitivity to DNA interstrand crosslink (ICL)-inducing agents. It was reported that variants in FANCM (MIM: 609644) might cause azoospermia or oligospermia. However, there is still a lack of evidence to explain the association between different FANCM variants and male infertility phenotypes. Herein, we identified compound heterozygous variants in FANCM in two NOA-affected brothers (c. 1778delG:p. R593Qfs*76 and c. 1663G > T:p. V555F), and a homozygous variant in FANCM (c. 1972C > T:p. R658X) in a sporadic case with NOA, respectively. H&E staining and immunohistochemistry showed Sertoli cell-only Syndrome (SCOS) in the three patients with NOA. Collectively, our study expands the knowledge of variants in FANCM, and provides a new insight to understand the genetic etiology of NOA.

Comparison Between Clinicopathological Characteristics, BRAF V600E and TERT Promoter Mutation of Familial Non-Medullary Thyroid Carcinomas, and Sporadic Case

BackgroundIt has been debated whether familial non-medullary thyroid carcinoma (FNMTC) is more aggressive and has a worse prognosis than sporadic non-medullary thyroid carcinoma (SNMTC). Our aim was to compare the invasiveness and prognosis of FNMTC and SNMTC by their biological behavior and molecular changes.Method and MaterialOur group mainly compared 106 patients with FNMTC whom have complete clinicopathological data during 2011–2019 in West China Hospital, Sichuan University, and 212 randomly selected cases with SNMTC were included to compare their biological behavior, recurrence and mortality, and molecular expression of BRAF V600E and TERT promoter. At the same time, FNMTC cases were divided into four subgroups, namely, two affected members group, three or more affected members, parent/offspring group, and sibling group, and they were compared with SNMTC separately to analyze the difference in their invasiveness and prognosis.ResultsWe found that the mean tumor size of FNMTC (0.96 ± 0.53cm) was smaller than that of SNMTC (1.15 ± 0.72 cm) (p = 0.020), while no significant difference in the incidence of other clinicopathological factors, including bilateral growth, capsular invasion, with thyroid nodular goiter or not, multifocality, lymph node metastasis, extrathyroidal extension, iodine 131 treatments, T stage, and American Joint Committee on Cancer (AJCC) stage, was observed between FNMTC and SNMTC (p > 0.05), between each FNMTC subgroup (p > 0.05), and between each FNMTC subgroup and SNMTC (p > 0.05). There was no significant difference in recurrence, mortality, and BRAF V600E and TERT promoter mutation between FNMTC and SNMTC, among which 50/60 (83.33%) of FNMTC patients had BRAF V600E mutation and 1/32 (3.13%) had TERT promoter mutation, while the mutation rates of SNMTC were 93/108 (86.11%) and 3/64 (4.69%) (p > 0.05).ConclusionThere was no significant difference in invasiveness and prognosis between FNMTC and SNMTC by biological behavior, patient survival, and molecular level comparison.

Human seasonal influenza under COVID-19 and the potential consequences of influenza lineage elimination

Annual epidemics of seasonal influenza cause hundreds of thousands of deaths, high levels of morbidity, and substantial economic loss. Yet, global influenza circulation has been heavily suppressed by public health measures and travel restrictions since the onset of the COVID-19 pandemic. Notably, the influenza B/Yamagata lineage has not been conclusively detected since April 2020, and A(H3N2), A(H1N1), and B/Victoria viruses circulate with considerably less genetic diversity. Travel restrictions have largely confined regional outbreaks of A(H3N2) to South and Southeast Asia, B/Victoria epidemics in China, and A(H1N1) in West Africa. Seasonal influenza transmission lineages continue to perish globally, except in select hotspots, which will likely seed future epidemics. Waning population immunity and sporadic case detection will further challenge influenza vaccine strain selection and epidemic control. We offer perspective on the potential short- and long-term evolutionary dynamics of seasonal influenza and discuss potential consequences and mitigation strategies as global travel gradually returns to pre-pandemic levels.

Heterozygous FMN2 Missense Variant Found in A Family Case of Premature Ovarian Insufficiency

Background Premature Ovarian Insufficiency plagues 1% of women under 40, while quite a few remain an unknown cause. The development of sequencing has helped find pathogenic genes and reveal the relationship between DNA repair and ovarian reserve. Through the exome sequencing, our study targets screening out the possible POI pathogenic gene and variants in a Chinese family and 20 sporadic POI patients, preliminarily exploring the functional impact and finding out potential linkages between the gene and POI. Results The whole exome sequencing suggested a novel FMN2 heterozygous variant c.1949C > T (p.Ser650Leu) carried by all three patients in a Chinese family and another c.1967G > A(p.Arg656His) variant in a sporadic case. Since no FMN2 missense mutation is reported for causing human POI, we preliminarily assessed p.Ser650Leu variant via cross-species alignment and 3D modeling and found it possibly deleterious. A series of functional evidence was consistent with our hypothesis. We proved the expression of FMN2 in different stages of oocytes and observed a statistical difference of chromosomal breakages between the POI patient carrying p.Arg656His variant and the health control (p = 0.0013). Western Blot also suggested a decrease in FMN2 and P21 in the mutant type and an associated increase in H2AX. The p.Arg656His variant with an extremely low frequency also indicated that the gene FMN2 might play an essential role in the genetic etiology of POI. To the best of our knowledge, this is the first POI report on missense variants of FMN2. Conclusion This finding indicates a novel gene possibly related to POI and sheds lights on the study of FMN2.

Giant pedunculated liver mass: primary hepatocellular carcinoma masquerading as hepatic haemangioma

A woman in her mid-60s was referred to surgeons with a 2-week history of worsening right-sided abdominal pain. CT demonstrated a large encapsulated, pedunculated hepatic lesion with active intracapsular bleeding and free fluid but nil further lesions. Findings suggested giant hepatic haemangioma; surgical excision took place the following day. Histopathology however confirmed malignancy. Pedunculated hepatocellular carcinoma (HCC) is rare but characteristically large and encapsulated. Sporadic case reports indicate that diagnosis is typically challenging and delayed with liver metastases at presentation. This case describes a patient with no clear risk factors for HCC found to have a well-defined, encapsulated and pedunculated mass but no detected metastasis or other lesions on initial CT. In this instance, subsequent MRI did identify further lesions in the liver. Such cases are limited in the literature: much remains to be learnt regarding presentation, differential diagnoses, investigation and management.

Tripod-shaped Syndactyly in Apert Syndrome with FGFR2 p.P253R Mutation

Apert syndrome is a rare acrocephalosyndactyly (craniosynostosis) syndrome characterized by craniofacial dysmorphism and syndactyly of the hands and feet. It is caused by FGFR2 mutations and inherited in an autosomal dominant manner. This article describes a novel clinical variant of Apert syndrome having bilateral symmetrical tripod-shaped syndactyly in hands with milder craniofacial features in a sporadic case, along with a mutation in the fibroblast growth factor receptor 2 (FGFR2) gene. The patient had shown craniosynostosis, dysmorphic face, ocular hypertelorism, marked depression of the nasal bridge, long philtrum, and low set ears. Direct resequencing of the FGFR2 gene through Sanger’s method identified a heterozygous missense mutation; FGFR2c.758C>G (FGFR2p.P253R) in the exon-7 of the gene.

Serological Evidence of Widespread Zika Transmission across the Philippines

Zika virus (ZIKV) exposure across flavivirus-endemic countries, including the Philippines, remains largely unknown despite sporadic case reporting and environmental suitability for transmission. Using laboratory surveillance data from 2016, 997 serum samples were randomly selected from suspected dengue (DENV) case reports across the Philippines and assayed for serological markers of short-term (IgM) and long-term (IgG) ZIKV exposure. Using mixture models, we re-evaluated ZIKV IgM/G seroprevalence thresholds and used catalytic models to quantify the force of infection (attack rate, AR) from age-accumulated ZIKV exposure. While we observed extensive ZIKV/DENV IgG cross-reactivity, not all individuals with active DENV presented with elevated ZIKV IgG, and a proportion of dengue-negative cases (DENV IgG-) were ZIKV IgG-positive (14.3%, 9/63). We identified evidence of long-term, yet not short-term, ZIKV exposure across Philippine regions (ZIKV IgG+: 31.5%, 314/997) which was geographically uncorrelated with DENV exposure. In contrast to the DENV AR (12.7% (95%CI: 9.1–17.4%)), the ZIKV AR was lower (5.7% (95%CI: 3–11%)) across the country. Our results provide evidence of widespread ZIKV exposure across the Philippines and suggest the need for studies to identify ZIKV infection risk factors over time to better prepare for potential future outbreaks.