different sample IDs between vcf and gtex gene count file

Question

[rheab1230]

Hello everyone, I have a vcf file and gene count file for gtex brain cortex tissue. My sample in gene count file is 255 whereas in vcf its only 205. I used sample attributes DS file to filter the gtex gene count file to contain only count coming from brain cortex tissue. there are 50 samples in my gene count file that doesn't match with the vcf. I used SMTSD AND SMTS to filter sample coming from brain cortex and then use SMAFRZE=="RNASEQ" so that i only get rnaseq gene count or samples.

sample_attributes_braindata <- sample_attributes %>% filter(sample_attributes$SMTS == "Brain" & sample_attributes$SMAFRZE == "RNASEQ" & sample_attributes$SMTSD=="Brain-Cortes"))
sample_attributes_braindata_cortex = sample_attributes_braindata[sample_attributes_braindata$SMTSD == "Brain - Cortex",]

Is there any other term that need to be included to further filter out these samples? Thank you.