2140 4: 5: 6: A. D65K (mutation to lysine) B. D65C (mutation to cysteine) C. D65A (mutation to alanine) D. D65S (mutation to serine) E. D65L (mutation to leucine) All of the following are clinical features of familial hypomagnesemic hypercalciuria with nephrocalcinosis (FHHNC), EXCEPT: A. Increased fractional excretion of Mg B. Rickets C. Decreased GFR D. Ocular abnormalities E. Deafness Which of the following treatments ameliorate the urinary Mg and Ca wasting in FHHNC? A. Thiazide diuretics B. Magnesium supplementation C. Amiloride D. Oral phosphate binders E. Kidney transplantation Which of the following claudins are selectively expressed in the neonatal kidney but not in adult kidney? A. B. C. D. E. Claudin-2 Claudin-7 Claudin-9 Claudin-16 Claudin-19 References 1. Rector FC Jr, Martinez-Maldonado M, Brunner FP, Seldin DW (1966) Evidence for passive reabsorption of NaCl in proximal tubule of rat kidney. J Clin Invest 45:1060–1070 2. 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