England boss Roy Hodgson will name his squad for the matches against Chile and Germany on Thursday and reports have suggested Berahino could be included.
But Downing, West Brom's joint assistant boss who coached Berahino at academy level, does not think the striker will get the nod.
"Any achievement like that would be fantastic for him, but whether they will do it, I have my doubts," he told the club's official website.
"I know people burst on the scene, but the national press had never heard of him a couple of months ago.
"Now they're trying to make a story about a boy-wonder, but I think Roy will have a level-headedness about him and know how the lad works, and I'm sure will make a calculated judgement.
"It would be great for the boy to have recognition - but is it feasible? I have my doubts about it."
Berahino, who has scored four goals in three appearances for England Under-21s, netted his sixth domestic goal of the campaign in Saturday's 2-0 win over rock-bottom Crystal Palace.
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