Most common mutation in Alpo syndrome is in COL4A5, which is transmitted as -

The inheritance is heterogeneous, being most commonly X-linked as a result of mutation of the gene encoding a5 type IV collagen. Males, therefore, tend to be affected more frequently and more severely than females and are more likely to develop renal failure. Ref: Robbins book of pathology. 9th edition. Page 53 Alpo syndrome: EM is diagnostic and shows "basket weave appearance" of the GBM. Alpo syndrome: Hereditary nephritis Abnormal a3 (COL4A3), a4 (COL4A4), or a5 (COL4A5) chain of type IV collagen Hematuria with progression to chronic renal failure Nerve deafness Eye disorders Foamy cells in the interstitium. Ref: RAM DAS NAYAK EXAM PREPARATORY MANUAL FOR UNDERGRADUATES 2nd ed. pg no: 612