What makes someone gay? Was it bad parenting, or too little love?

Almost no one asks “what makes someone straight?” The fact that the question only runs one way already gives something away: whoever’s asking usually starts from “straight is the default, and gay is the thing that needs explaining.” Drop that assumption and the question turns ordinary — it belongs in the same bin as “why do people come in different heights, or favor different hands?” The honest answer is: they just do.

And truthfully, science doesn’t have one clean answer here — which is completely normal. Plenty of complex human traits have no single switch.

Where the evidence actually points

• Nature carries real weight. Studies of twins and families consistently find that orientation is moderately heritable — note, it contributes, it doesn’t decide. There’s no on/off “gay gene”; it looks more like a leaning that many small factors add up to.
• A lot of the trail leads to before birth. Prenatal developmental factors, such as the hormonal environment, come up again and again — and all of that happens before a person has any “experiences” at all.
• It isn’t taught, and it isn’t picked up like a bad habit. After weighing the evidence, the APA is blunt: no research shows that orientation is set by a style of parenting or a particular childhood event. An absent father, a single parent, someone’s “influence” — the most widely repeated explanations are exactly the ones with the least evidence behind them.

Why “finding the cause” is often really about something else

Chasing “but what caused it” is frequently less about understanding than about repair — locate the “root,” then talk about a “fix.” That road is wrong from the first step: orientation isn’t a malfunction and needs no etiology (for why “fixing” it doesn’t hold up, see Can orientation be changed?).

Other times, hunting for a cause is a way of assigning guilt. Parents especially tend to read a child’s orientation as a report card on their parenting. But gay and straight parents alike have raised children of every orientation — a parent’s orientation doesn’t even determine a child’s, so a few shortfalls of affection certainly won’t. And the idea that some romantic wound “turned” someone doesn’t add up either (see Do women love women because a man hurt them?).

If what you’re really looking for is “who to blame”

Then here’s the answer: no one is — not you, and not your parents. Trading “why am I like this” for “how can I live well” is usually the more worthwhile question to spend energy on. To understand the concept of orientation from the ground up, read orientation basics.