The lesson “X-linked recessive inheritance” is interdisciplinary, part of the curriculum of the innovative subject of Science and technology. It is based on Content Language Integrated Learning and not only combines subject content and foreign language skills, but unites more than one scientific field. In our case, we examined a biological process through the lens of the English language and in a historical context. This provided a deeper understanding of the processes in our surroundings, proving that nothing operates in isolation, but in constant and predictable connections with the world around us. The topic deals with basic concepts of genetics in English, tracing the ability of recessive genes on the X-chromosome to be inherited only by the female descendants. We worked with VIII grade students, for whom this lesson was their first encounter with genetics. The content of all lesson material is adapted to the age and grade of the students.