In the Bible, the word "flesh" is used for the human body and for the sinful nature. But ones interpret this to mean the physical flesh is the problem. My opinion is there is our spiritual level of "flesh". It means whatever in us is capable of sinning, meaning at our spiritual level. But yes we have ones who blame the physical flesh for our sin problems

But it is not our physical DNA that passes on the spiritual problem of sin, I offer. But there is "the spirit who now works in the sons of disobedience," our Apostle Paul mentions in Ephesians 2:2. My opinion is that parents with this disobedient spirit can infect their conceived children, right from conception. And this is why children very young already can be so about their own selves and able to lie and scream for their own way, versus having a natural tendency to share and care in love as family.
Below, I have quoted how Clare does not at all agree with this.