gistfile1.clj

(defn overall-rank [cards]
  (sum (map :rank cards))

(defn of-a-kind [n hand]
  (->> (group-by :rank hand)
       (vals)
       (sort-by overall-rank)
       (filter #(= n (count %)))))

(defn pairs [hand]
  (of-a-kind 2 hand))

(defn threes [hand]
  (of-a-kind 3 hand))

(defn independent? [xs ys]
  (empty? (set/intersection (set xs) (set ys))))

(defn full-houses [hand]
  (sort-by overall-rank
    (for [[t p] (threes hand) (pairs hand) :when (independent? t p)]
      (concat t p))))

(defn independant? [xs ys]
  (not= (set xs) (set ys))

Your independent? method wouldn't work with overlaps:

(independent? '(5H 5C 5D) '(5C 5D))