title: Illumina NovaSeq 6000 paired end sequencing; multiomic snRNAseq/snATACseq of first and second-trimester human gonads
design: multiomic snRNAseq/snATACseq of first and second-trimester human gonads
library_construction_protocol: All tissue samples used for this study were obtained with written informed consent from all participants in accordance with the guidelines in The Declaration of Helsinki 2000.Human embryo and fetal samples were obtained from the MRC and Wellcome-funded Human Developmental Biology Resource (HDBR, http:// www.hdbr.org), with appropriate maternal written consent and approval from the Fulham Research Ethics Committee (REC reference 18/LO/0822) and Newcastle & North Tyneside 1 Research Ethics Committee (REC reference 18/NE/0290). The HDBR is regulated by the UK Human Tissue Authority (HTA; www.hta.gov.uk) and operates in accordance with the relevant HTA Codes of Practice.All tissues for sequencing and spatial work were collected in HypoThermosol biopreservation media and stored at 4°C until processing. Tissue dissociation was conducted within 24 hours of tissue retrieval with the exception of tissues that were cryopreserved and stored at -80°C. Single-nuclei suspensions were isolated from frozen tissue sections when performing multiomic snRNA-seq/scATAC-seq. Thick (300 µm) sections were cryosectioned, and kept in a tube on dry ice until subsequent processing. Nuclei were released via Dounce homogenisation as described in detail in the protocols.io of PMID:26890679 For snRNA-seq/scATAC-seq experiments, cells were loaded according to the manufacturer's protocol for the Chromium Single Cell Multiome ATAC + Gene Expression v1.0 to attain between 2,000 and 10,000 nucleus per well.