Table 1.

Main clinical features and indications for treatment in osteopetrosis.

Gene	Autosomal recessive osteopetrosis	Overall disease severity	Hematological defects	Visual defects	Hypocalcemia	Growth retardation	Primary neurodegeneration	Indication to HSCT
TCIRG1	Osteoclast-rich form	Most often severe	Severe	Mild to severe	Severe	Mild to severe	No	Yes
ClCN7	Osteoclast-rich form	Severe to mild	Mild to severe	Mild to severe	Severe	Mild to severe	Yes	To be evaluated based on the severity of CNS involvement
OSTM1	Osteoclast-rich form	Severe	Mild to severe	Mild to severe	Moderate	Mild to severe	Yes	No severe CNS involvement
SNX10	Osteoclast-rich form	Variable	Severe	Severe	Mild	Mild	No	Yes
CAII	Osteoclast-rich form	Moderate	None	Mild	Mild	Moderate	Cerebral calcification	To be evaluated based on cerebral calcification
PLEKHM1	Osteoclast-rich form	Mild	None	None	None	None to moderate	No	No mild presentation
FERMT3	Osteoclast-rich form	Severe	Severe	Mild	Mild	Mild	No	Yes
NEMO	Osteoclast-rich form	Severe	Severe	None	Mild	Moderate	No	Yes
TNFRSF11A/RANK	Osteoclast-poor form	Most often severe	Mild	Mild	Mild	Moderate	No	Yes
TNFSF11/RANKL	Osteoclast-poor form	Intermediate	Mild	Mild	Mild	Severe	No	No