Læknablaðið : fylgirit - 01.06.1982, Blaðsíða 44

31
AN IŒLANDIC FAMILY WITH ELEVATED THYROXIN BINDING GLOBULIN
WITH X CHROMOSOME LINKED INHERITMCE. Gudni A Sigurdsson,
Gudmundur Amason, Thorvaldur Veigar Gudmundsson, Matthias
Kjeld, Gunnar Sigurdsson. Akranes Hospital, The National
Hospital and Reykjavik City Hospital.
An Icelandic family with oongenital elevaticn of
thyroxin binding globulin is described vdiere 16 out of 33
menibers of the family of four generations vere affected. Both
sexes were involved, women transmitted to both sons and
daughters vhereas affected males transmitted to daughters, but
not to sons. Males showed full expression of the trait vdiereas
it was more variable in women. This kind of inheritance and
the variability of expression in the heterozygous wcæn is in
keeping with other X chromosome linked traits.
Qnly 12 families with this disorder have been described
in the literature, but the condition may be more ccnnron as it
is usually asyirptomatic. This ccndition underlines the
importance of other thyroid function tests than the usual
total serum thyroxin and trijodothyronin.