ensembl下载基因组序列：
wget -c https://ftp.ensembl.org/pub/release-114/fasta/mus_musculus/dna/Mus_musculus.GRCm39.dna.toplevel.fa.gz
wget -c https://ftp.ensembl.org/pub/release-114/gtf/mus_musculus/Mus_musculus.GRCm39.114.chr.gtf.gz
gunzip Mus_musculus.GRCm39.114.chr.gtf.gz
#保留染色体部分序列
seqkit grep -r -p "^[0-9]+" -p "X" -p "Y" -p "MT" Mus_musculus.GRCm39.dna.toplevel.fa.gz >Mus_musculus.GRCm39.dna.toplevel.fa
saw makeRef \
--mode=STAR \
--fasta=Mus_musculus.GRCm39.dna.toplevel.fa \
--gtf=Mus_musculus.GRCm39.114.chr.gtf \
--genome=MM_GRCm39
