col 1: pedigree ID
col 2: person ID
col 3: gender (1 for male, 2 for female)
col 4: age at interview
col 5: diagnostic string (a string identifier)
col 6: age at onset of disease (0 for unaffecteds)
col 7: age at the first attack or sympton of disease
	(0 for unaffecteds)


a sample file:
EX2 0001 1 56.5 AFF_DEF 28 18
EX2 0002 2 51.3 AFF_UNK  0  0
EX2 0004 1 48.1 AFF_PRB 26 30
EX2 0005 1 40.6 AFF_NO   0  0
EX2 0006 1 66.0 AFF_UNK  0  0
EX2 0007 2 76.3 AFF_PRB  0  0
EX2 0008 1 0.0  AFF_POS  0  0
EX2 0009 2 32.9 AFF_PRB 34 24
EX2 0010 1 28.6 AFF_NO   0  0