Metabolic and immune development in neonates are shaped by the succession of the gut microbiome. Maternal obesity can perturb this process by altering interactions of human milk bioactive elements, including oligosaccharides (HMOs), microbial populations, and metabolites. We conducted a longitudinal study of Mexican mother-infant dyads to examine maternal BMI-associated variations in HMOs and infant fecal microbiota. Breastmilk samples from 97 mothers were collected at 48 h, one month, and three months postpartum. We used targeted and untargeted metabolomics to profile breastmilk samples, while shotgun metagenomics was used to analyze infant fecal microbiome composition in a subset of samples. Mothers with obesity showed decreased concentration of key HMOs shortly after birth, correlating with an altered succession of their infant's gut microbiota. This included reduced early colonizers (Enterobacteriaceae) and increased abundance of intermediate and late colonizers (Bifidobacterium and members of the Lachnospiraceae family), over subsequent months. These taxa negatively correlated with HMOs such as 6'SL, LNnT, and LNT. Additionally, functional profiling revealed alterations in metabolic pathways related to polyamine biosynthesis, suggesting changes in microbial metabolism linked to maternal BMI. Despite the cohort's size, our study offers unique insights into the relationship between maternal obesity, HMO composition, and early infant microbial colonization in Latin-American mothers. This exploratory research serves as proof of concept, underscoring the need for larger-scale studies to validate these findings and better understand their implications for infant health. More importantly, our results highlight the interplay between maternal BMI and human milk bioactives, underscoring the importance of correlating microbial succession with maternal metabolic health to better understand early immune development in neonates.
We report a 5-year-old Spanish male with a homozygous SPOUT1 variant (NM_016390.4:c.1058C>T; p.Thr353Met), identified by re-analysis of whole-genome sequencing. His phenotype includes severe developmental delay, microcephaly, epilepsy evolving to Lennox-Gastaut-like syndrome, growth impairment, dysmorphic features, and multiple congenital anomalies. Our case expands the SPOUT1-related neurodevelopmental spectrum and underscores the diagnostic value of periodic genomic data re-analysis.
INTRODUCTION:The most frequent form of diabetes in pediatric patients is polygenic autoimmune diabetes (type 1 diabetes [T1D]), but single-gene variants responsible for autoimmune diabetes have also been described. Both disorders share clinical features, which can lead to monogenic forms being misdiagnosed as T1D. However, correct diagnosis is crucial for therapeutic choice, prognosis, and genetic counseling. The aim of this study was to search for monogenic autoimmune diabetes in Spanish pediatric patients with early-onset T1D. METHODS:Among 500 Spanish pediatric patients with T1D, those with disease onset between 9 and 30 months of age were selected for screening for monogenic autoimmune diabetes (n = 44). Genetic testing was performed by next-generation sequencing with a customized panel that included the major causative genes for monogenic autoimmune syndromes, including early-onset diabetes: AIRE, CTLA4, FOXP3, IL2RA, ITCH, LRBA, STAT1, STAT3, STAT5B. RT-PCR and cDNA sequencing of the RNA isolated from whole blood were used to analyze splicing variants. RESULTS:Genetic screening identified, in 2 patients with diabetes onset before 1 year of age, 2 likely pathogenic novel variants affecting canonical splicing sites: c.286-12_290del in STAT5B and c.-22-2delA in FOXP3. RNA analyses demonstrated that both variants modify mRNA splicing. The variant in STAT5B induced exon 4 skipping and the variant in FOXP3 caused a deletion of 16 nucleotides before the transcription start site. CONCLUSION:T1D onset in the first year of life may indicate monogenic autoimmune diabetes and molecular testing may be recommended.
