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Biology subjects

Dattani, M. T.

Publications and source records attributed to Dattani, M. T..

2 recordsLinked to original sources

Sex differences in early human fetal brain development

The influence of sex chromosomes and sex hormones on early human brain development is poorly understood. We therefore undertook transcriptomic analysis of 46,XY and 46,XX human brain cortex samples (n=64) at four different time points between 7.5 and 17 weeks post conception (wpc), in two independent studies. This developmental period encompasses the onset of testicular testosterone secretion in the 46,XY fetus (8wpc). Differences in sex chromosome gene expression included X-inactivation genes (XIST, TSIX) in 46,XX samples; core Y chromosome genes (n=18) in 46,XY samples; and two Y chromosome brain specific genes, PCDH11Y and RP11-424G14.1. PCDH11Y (protocadherin11 Y-linked) regulates excitatory neurons; this gene is unique to humans and is implicated in language development. RP11-424G14.1 is a novel long non-coding RNA. Fewer differences in sex hormone pathway-related genes were seen. The androgen receptor (AR, NR4A2) showed cortex expression in both sexes, which decreased with age. Global cortical sex hormone effects were not seen, but more localized AR mechanisms may be important with time (e.g., hypothalamus). Taken together, our data suggest that limited but potentially important sex differences occur during early human fetal brain development.

developmental biology↗

Mapping the anatomical and transcriptional landscape of early human fetal ovary development

The complex genetic mechanisms underlying human ovary development can give rise to clinical phenotypes if disrupted, such as Primary Ovarian Insufficiency and Differences of Sex Development. Through a clinically-focused lens, we combine single-nuclei RNA sequencing, bulk RNA sequencing, and micro-focus computed tomography to elucidate the anatomy and transcriptional landscape of the human fetal ovary across key developmental timepoints (Carnegie Stage 22 until 20 weeks post conception). We show the marked growth and distinct morphological changes within the fetal ovary at the critical timepoint of germ cell expansion, and demonstrate that the fetal ovary becomes more transcriptomically distinct from the testis with age. We describe novel ovary developmental pathways, relating to neuroendocrine signalling, energy homeostasis, mitochondrial networks, piRNA processes, and inflammasome regulation. We define transcriptional regulators and candidate genes for meiosis within the developing ovary. Together, this work advances our fundamental understanding of human ovary development and clinical ovarian insufficiency phenotypes.

genomics↗