Heighington, a 28-year-old loose forward who has made almost 200 appearances in the NRL, will arrive in the UK in early October to join the train-on squad which begins assembling this week.
Although born in Sydney, Heighington has dual nationality through his English father and confirmed his desire to play for England earlier this year.
“I’m delighted that Chris wants to play for England, he’s an outstanding player who I’m really looking forward to working with during the fall-out programme and perhaps beyond,” said McNamara.
“His work-rate and work ethic are first class and I’m sure those qualities will enhance the Elite Training Squad as we strive to achieve international success.
“I spoke to Chris at length when I visited Australia in the spring and it was clear that his motives in wanting to play for England were right: he’s very proud of his English roots and he wants to make a difference to the England team.”
Heighington’s father Tom emigrated to Australia in his early-20s from County Durham, an area the family have retained strong links with, including their association with the village of Heighington near Darlington.
“Playing for England is something that’s been on my mind for a good few years now and if I get the chance I’ll be very proud,” said Heighington, a Wests Tigers team-mate of established England second row Gareth Ellis.
“When Steve came over before the start of the season we had a long chat and it became clear to me that this is what I want to do.
“I’d like to be given the opportunity to help England achieve international success and I’m sure the other England players will see that. I’m going to train hard and work hard and show everyone, not just Steve, that I’m worthy of an England jersey in the Four Nations.”
Heighington’s call-up comes just a few days after Airedale-born Brisbane Broncos centre Jack Reed pledged his allegiance to his country of birth ahead of the Four Nations in the UK later this year, when England face Australia, New Zealand and Wales.
RFL Chief Executive Nigel Wood said that whilst he understood the presence of Heighington in the England camp would fuel a debate about international selection, any arguments were purely philosophical.
“The international eligibility rules are clear and we should play by them in selecting the strongest team available to us,” said Wood.
“Other nations have used the rules to their advantage for many years now and it is right that we do the same.
“There is no change of policy: we remain committed to increasing the quantity and quality of club trained talent and our commitment to programmes like the Elite Training Squad is undiminished.”