What is the sum that client number 4's account has following transaction 851? Who owns this account, a man or a woman?
SELECT T3.balance, T1.gender FROM client AS T1 INNER JOIN account AS T2 ON T1.district_id = T2.district_id INNER JOIN trans AS T3 ON T2.account_id = T3.account_id WHERE T1.client_id = 4 AND T3.trans_id = 851