Screening for mutations in the ISL1 gene in patients with thyroid dysgenesis.
BACKGROUND
Congenital hypothyroidism (CH) is a common endocrine disorder with an incidence of 1:3000- 4000 newborns. In 80-85% of cases, CH is caused by defects in thyroid organogenesis, resulting in absent, ectopically located, and/or severely reduced gland, all conditions indicated as "thyroid dysgenesis" (TD). A higher prevalence of congenital heart diseases has been documented in children with CH compared to the general population. This association suggests a possible pathogenic role of genes involved in both heart and thyroid development. Among these, it can be included Isl1, a transcription factor containing a LIM homeodomain that is expressed in both thyroid and heart during morphogenesis.


OBJECTIVE
In the present study, we investigate the role of ISL1 in the pathogenesis of TD.


METHODS
By single stranded conformational polymorphism, we screened for mutations the entire ISL1 coding sequence in 96 patients with TD and in 96 normal controls.


RESULTS
No mutations have been found in patients and controls.


CONCLUSIONS
Our data indicate that, despite the relevant role of ISL1 in thyroid and heart morphogenesis, mutations in its coding region are not associated with TD in our group of patients.
Department of Endocrinology and Molecular and Clincal Oncology, Federico II Univerity of Naples, Naples - Italy.
A M
AM
Ferrara
G
G
Rossi
E
E
Zampella
S
S
Di Candia
V
V
Pagliara
I C
IC
Nettore
D
D
Capalbo
L
L
De Sanctis
M
M
Baserga
M C
MC
Salerno
G
G
Fenzi
P E
PE
Macchia
D000818:Animals; D004252:DNA Mutational Analysis; D020022:Genetic Predisposition to Disease; D006801:Humans; D060850:LIM-Homeodomain Proteins / Q000235:genetics*; D009154:Mutation; D018807:Polymorphism, Single-Stranded Conformational; D050033:Thyroid Dysgenesis / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics*
D060850:LIM-Homeodomain Proteins; D014157:Transcription Factors; C063843:insulin gene enhancer binding protein Isl-1