Category Archive: Reproduction

Jul 28 2014

What’s wrong with rainbow families?

A woman went to a fertility clinic for artificial insemination, and discovered a surprising stipulation. She’s white, so they’ll only allow her access to sperm from white men. Dr. Calvin Greene, the clinic’s administrative director, confirmed the private facility will not treat couples or singles who insist on using donors of a different ethnicity. The …

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Apr 06 2014

The abortion problem…solved!

Dana publishes the simple, brilliant solution to abortion. I can’t see any downside to it. We already live in a culture where pointless surgical alterations to boy’s genitals are common, and this just adds one more. I’m thinking we could also make it a ritual of passage into manhood. You aren’t really a man until …

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Apr 04 2014

I’m feeling really filthy now

Mississippi has horrific rates of teen pregnancy and sexually transmitted diseases, so they’re slowly waking up and realizing that they have to have better sex education in the schools … and they’ve actually adopted a sex-ed curriculum in some of their school districts. Unfortunately, it’s not what most of us would consider good education. Marie …

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Mar 11 2014

Pathways to sex

The molecular and genetic events in mammalian sex determination. The bipotential genital ridge is established by genes including Sf1 and Wt1, the early expression of which might also initiate that of Sox9 in both sexes. b-catenin can begin to accumulate as a response to Rspo1–Wnt4 signaling at this stage. In XX supporting cell precursors, b-catenin levels could accumulate sufficiently to repress SOX9 activity, either through direct protein interactions leading to mutual destruction, as seen during cartilage development, or by a direct effect on Sox9 transcription. However, in XY supporting cell precursors, increasing levels of SF1 activate Sry expression and then SRY, together with SF1, boosts Sox9 expression. Once SOX9 levels reach a critical threshold, several positive regulatory loops are initiated, including autoregulation of its own expression and formation of feed-forward loops via FGF9 or PGD2 signaling. If SRY activity is weak, low or late, it fails to boost Sox9 expression before b-catenin levels accumulate sufficiently to shut it down. At later stages, FOXL2 increases, which might help, perhaps in concert with ERs, to maintain granulosa (follicle) cell differentiation by repressing Sox9 expression. In the testis, SOX9 promotes the testis pathway, including Amh activation, and it also probably represses ovarian genes, including Wnt4 and Foxl2. However, any mechanism that increases Sox9 expression sufficiently will trigger Sertoli cell development, even in the absence of SRY.

I was talking about sex and nothing but sex all last week in genetics, which is far less titillating than it sounds. My focus was entirely on operational genetics, that is, how autosomal inheritance vs inheritance of factors on sex chromosomes differ, and I only hinted at how sex is not inherited as a simple …

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Mar 05 2014

Crazy, obsessed, weird, perverse


Sometimes those are good descriptors. I read a happy story for a change this morning: it’s about Arunachalam Muruganantham, an Indian man who embarked on a long crusade to make…sanitary napkins. Perhaps you laugh. Perhaps you get a little cranky at a guy who rushes in to meddle in women’s concerns. And there’s some good …

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Apr 19 2013

Also, I know I’ll probably get flamed for this…

But after this week I just don’t care. PZ can feed me to the squids if he wants to. I just don’t care.

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Apr 10 2013

Well, when you put it that way…


I’m sure there’s nothing wrong with this logic.

Mar 13 2013

Strident Catholics hurt my brain


I can call them ‘strident,’ can’t I? They apply it to atheists all the time, and this is clearly a case where the adjective is perfectly appropriate. It’s an opinion piece by a militant (I can use that, too!) Catholic who traces the fall of America to a court decision in 1972. This year, the …

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Mar 06 2013



An organization called the Susan B. Anthony List — it’s an adamantly anti-choice group that has neatly named itself after an icon of women’s liberation — has a wonderful president, Marjorie Dannenfelser, who not only opposes abortion, but is dead set against contraception. She argues here that increasing availability of contraception leads to increasing rates …

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Jan 25 2013

Science doesn’t say that!

Have you ever noticed how the religious regard ‘scientism’ and ‘reductionism’ and demands for concrete evidence as barely a notch above obscenities? That is, until they need to reduce complex issues to simplistic claims and don the mantle of Science to support their beliefs. Then they become Holy Writ. You can really see this behavior …

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