Biology question.. I got curious

[untoldbattles]

So I happen to be studying about genetics and inheritance in my class.. and a section talks about the enzyme telomerase. I understand that telomerase is not active in most human somatic cells except in rapidly dividing ones such as bone marrow cells etc. However, they are active in germ cells resulting in them having maximum telomere lengths. If this is the case, are germ cells basically immortal? And if so, why does infertility arise then? Is the deterioration of fertility in humans due to other factors and not the germ cells themselves?

P.s These aren't questions from my assignments or anything, I'm just curious as I can't seem to find a conclusive answer online

[tiptoes]

From what I understand with replication you can lose some of the telomeric DNA. By germ cells do you mean eggs and sperm? In which case I think that they have the longest lengths as it is the replication of these cells which give you a baby and therefore their DNA will have been replicated oodles of times.

Telomeric aging has been postulated as a reason for cloned animals dying prematurely as the were grown out of adult cells and thus would have shorter lengths of telomeric DNA.

There are quite a number of reasons for infertility I don't think telomere length play a role. One of the reasons is that eggs die or become poor quality with age. The quantity and quality of the sperms cells can also play a role as can the environment of the womb for implantation.

[untoldbattles]

Quote:

Originally Posted by tiptoes

From what I understand with replication you can lose some of the telomeric DNA. By germ cells do you mean eggs and sperm? In which case I think that they have the longest lengths as it is the replication of these cells which give you a baby and therefore their DNA will have been replicated oodles of times.

Telomeric aging has been postulated as a reason for cloned animals dying prematurely as the were grown out of adult cells and thus would have shorter lengths of telomeric DNA.

There are quite a number of reasons for infertility I don't think telomere length play a role. One of the reasons is that eggs die or become poor quality with age. The quantity and quality of the sperms cells can also play a role as can the environment of the womb for implantation.

Yeah, by germ cells I'm referring to the sperms and eggs. Hm I see, thank you for the information!

[effervescence]

There are a LOT of factors influencing fertility.

A man might have sperm cells with normal DNA but not enough of them so is ejaculate is "too dilute". The DNA might be normal but the tails aren't formed so they can't swim. etc etc.

A woman may have perfect eggs but her fallopian tubes are blocked. She may have polycystic ovaries, or something else wrong meaning the eggs don't release properly. Her hormones may be off so that her uterus does not allow the fertilised egg to implant. Her cervix may shorten abnormally leading to recurrent miscarriage. etc etc.

Add to this other factors such as increasing maternal age, higher BMIs, smoking, increases in other medical conditions such as heart disease and diabetes which all affect your ability to conceive and then to carry a healthy pregnancy.