How many letters does the top answer for “an inherited form of anemia caused by faulty synthesis of hemoglobin” have?

The most common answer is thalassaemia (12 letters).

Crossword clue: an inherited form of anemia caused by faulty synthesis of hemoglobin

2 answers found in Letterora's clue database (Wikidata facts, Open Trivia DB, WordNet and Webster definitions — all licensed sources).

thalassaemia 12 letters wn-def

an inherited form of anemia caused by faulty synthesis of hemoglobin

thalassemia 11 letters wn-def

an inherited form of anemia caused by faulty synthesis of hemoglobin