Researchers exploring risky decision-making in rats found that a specific reward-related neural circuit influences impulsivity and risk-taking in complex ways that depend on timing and biological sex.
Category: sex
Spaceflight study reveals men experience greater eye changes, while brain differences between sexes are subtle
A new study into how spaceflight impacts the human brain and eyes revealed notable sex differences in brain fluid shifts, with female astronauts showing a greater reduction in fluid around the uppermost part of the brain than their male counterparts.
Led by Rachael D. Seidler, Ph.D., director of the University of Florida’s Astraeus Space Institute and professor of applied physiology and kinesiology, the study analyzed data from astronauts to determine how factors such as sex, age and body metrics relate to structural brain and eye changes after space travel.
The findings, published in npj Microgravity, provide key information for protecting astronaut health on long-duration missions to the moon and Mars.
In-utero exposure to maternal diabetes and DNA methylation alterations in the Next Generation birth cohort
The incidence of type 2 diabetes (T2D) in youth is increasing and in-utero exposure to maternal diabetes is a known risk factor, with higher risk associated with pregestational T2D exposure compared to gestational diabetes mellitus (GDM) exposure. We hypothesize this differential risk is reflected in DNA methylation (DNAm) changes induced by differential timing of in-utero exposure to maternal diabetes, and that exposure to diabetes throughout pregnancy (T2D) compared to exposure later in development (GDM), induces different DNAm signatures and different T2D risk to offspring. This study presents an epigenome-wide investigation of DNAm alterations associated with in-utero exposure to either maternal pregestational T2D or GDM, to determine if the timing of prenatal diabetes exposure differentially alters DNAm.
We performed an epigenome-wide analysis on cord blood from 99 newborns exposed to pregestational T2D, 70 newborns exposed to GDM, and 41 unexposed to diabetes in-utero from the Next Generation birth cohort. Associations were tested using multiple linear regression models while adjusting for sex, maternal age, BMI, smoking status, gestational age, cord blood cell type proportions and batch effects.
We identified 27 differentially methylated sites associated with exposure to GDM, 27 sites associated with exposure to T2D, and 9 common sites associated with exposure to either GDM or T2D (adjusted p value 0.01). One site at CLDN15 and two unannotated sites were previously reported as associated with obesity. We also identified 87 differentially methylated regions (DMRs) associated with in-utero exposure to GDM and 69 DMRs associated with in-utero exposure to T2D. We identified 23 DMR sites that were previously associated with obesity, three with T2D and five with in-utero exposure to GDM. Furthermore, we identified six CpG sites in the PTPRN2 gene, a gene previously associated with DNAm differences in blood of youth with T2D from the same population.
Social conflict among strongest predictors of teen mental health concerns, research shows
Approximately 20% of American adolescents experience a mental health disorder each year, a number that has been on the rise. Genetics and life events contribute, but because so many factors are involved, and because their influence can be subtle, it’s been difficult for researchers to generate effective models for predicting who is most at risk for mental health problems.
A new study from researchers at Washington University School of Medicine in St. Louis provides some answers. Published Sept. 15 in Nature Mental Health, it mined an enormous set of data collected from pre-teens and teens across the U.S. and found that social conflicts—particularly family fighting and reputational damage or bullying from peers—were the strongest predictors of near-and long-term mental health issues.
The research also revealed sex differences in how boys and girls experience stress from peer conflict, suggesting that nuance is needed when assessing social stressors in teens.
Analysis of genomic heterogeneity and the mutational landscape in cutaneous squamous cell carcinoma through multi-patient-targeted single-cell DNA sequencing
Cutaneous squamous cell carcinoma (CSCC) is a prevalent skin cancer with aggressive progression that poses significant challenges, especially in metastatic cases. Single-cell DNA sequencing (scDNA-seq) has become an advanced technology for elucidating tumor heterogeneity and clonal evolution. However, comprehensive scDNA-seq studies and tailored mutation panels for CSCC are lacking.
We analyzed the genomic landscape of Chinese CSCC patients via a Multi-Patient-Targeted (MPT) scDNA-seq approach. This method combined bulk exome sequencing with Tapestri scDNA-seq. Mutations identified through bulk sequencing were used to design a targeted panel for scDNA-seq. Comparative analysis was conducted to explore the associations between specific gene mutations and clinical characteristics such as tumor stage and patient sex. Clonal evolution analysis was performed to understand the evolutionary trajectories of the tumors.
Bulk sequencing revealed a diverse spectrum of somatic mutations in CSCC tumors, with missense mutations being predominant. The top tumor mutations, such as those in NOTCH1, TP53, NOTCH2, TTN, MUC16, RYR2, PRUNE2, DMD, HRAS, and CDKN2A, presented similar frequencies to those reported in studies in Korean and Caucasian populations. However, the mutation frequencies of HRAS, TTN, MUC16 and MUC4 were significantly different from the Korean and Caucasian populations. Comparative analysis revealed associations between specific gene mutations and clinical characteristics such as tumor stage and patient sex. Clonal evolution analysis via scDNA-seq revealed distinct evolutionary trajectories and their potential correlation with tumor development and patient prognosis. Furthermore, scDNA-seq identified two low-frequency mutation clones, NLRP5 and HMMR, which play important roles in the clonal evolution of CSCC.
How hair and skin characteristics affect brain imaging: Making fNIRS research more inclusive
Functional near-infrared spectroscopy (fNIRS) is a promising non-invasive neuroimaging technique that works by detecting changes in blood oxygenation linked to neural activity using near-infrared light. Compared to fMRI and various other methods commonly used to study the brain, fNIRS is easier to apply outside of laboratory settings.
This technique requires study participants to wear a special cap fitted with optodes, which consist of light sources that emit near-infrared light into the scalp and detectors that measure the light that is reflected back. These measurements can be used to estimate blood oxygenation in the brain’s outer layers. Despite its potential for conducting research in everyday settings, the quality of signals collected using fNIRS is known to be influenced by biophysical factors.
A team of researchers at Boston University recently set out to better delineate the extent to which people’s hair and skin color, age and sex impact the quality of fNIRS signals picked up from their scalp.
Depression genetics differ by sex: Study find females carry higher risk than males do
Important genetic differences in how females and males experience depression have been revealed for the first time in findings that could pave the way for more targeted intervention and treatments.
In the study, published in Nature Communications, scientists found that genetic factors contribute more to depression risk in females than in males. The team discovered about twice as many genetic “flags” for depression in the DNA of females as they did in that of males.
“We already know that females are twice as likely to suffer from depression in their lifetime than males,” said Dr. Brittany Mitchell, Senior Researcher at QIMR Berghofer’s Genetic Epidemiology Lab. “And we also know that depression looks very different from one person to another. Until now, there hasn’t been much consistent research to explain why depression affects females and males differently, including the possible role of genetics.”
A single gene may explain why immune responses differ between men and women
A new study has uncovered a key difference between the immune system of males and females—and it comes down to a single gene. The study is published in The Journal of Immunology.
It is known that biological sex affects the function of the immune system, with women often being more severely affected by autoimmune conditions or allergic diseases.
Scientists from the University of York have now identified the gene Malat1 as a critical player in regulating immune responses in female immune cells, but not in males.