// A *self-contained* demonstration of the problem follows...
class Other extends React.Component<any, any> {
	render() {
		return <div />;
	}
}

class Container extends React.Component<any, any> {
	private _ref: Other;

	render() {
                // Parameter 'ref' implicitly has an 'any' type.
		return <Other ref={ ref => this._ref = ref } />;
	}
}