Identification of two novel mutations in the 5'-untranslated region of H-ferritin using denaturing high performance liquid chromatography scanning.
OBJECTIVE
Hereditary hyperferritinemia cataract syndrome is caused by mutations of the iron responsive elements (IREs) of L-ferritin mRNA. These alter the IRE structure and determine L-ferritin upregulation. IREs are located in 5'untranslated regions (5'UTR) of ferritin mRNAs. L-ferritin 5'UTR has been extensively studied and up to 21 different mutations have been identified. Only one mutation has been reported for H-ferritin 5'UTR; this mutation modified IRE structure and was apparently associated with high serum ferritin levels and iron overload.


METHODS
To identify other mutations in H ferritin 5'UTR we developed a fast DNA scanning method based on denaturing high performance liquid chromatography (HPLC). Five artificial DNA mutants were produced in order to validate the analytical conditions of the system for the identification of all mutations by single runs at 68 degrees C. The system was used to screen 660 DNA samples from subjects with high serum ferritin levels.


RESULTS
Two abnormal patterns were identified carrying the mutations C20G and G34T. Structural data and the analysis of ferritin levels in red blood cells suggest that these mutations do not affect the functionality of the IRE.


CONCLUSIONS
This large and first population analysis indicates that mutations in the H-ferritin 5'UTR are rare and do not seem to contribute to hyperferritinemia or iron overload.
Cremonesi
Laura
L
IRCCS H. San Raffaele, Unit of Genomics for Diagnosis of Human Pathologies, Milan, Italy.
Foglieni
Barbara
B
Fermo
Isabella
I
Cozzi
Anna
A
Paroni
Rita
R
Ruggeri
Giuseppina
G
Belloli
Silvana
S
Levi
Sonia
S
Fargion
Silvia
S
Ferrari
Maurizio
M
Arosio
Paolo
P
D020121:5' Untranslated Regions / Q000235:genetics*; D000368:Aged; D001483:Base Sequence / Q000235:genetics; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004247:DNA / Q000235:genetics; D005260:Female; D005293:Ferritins / Q000235:genetics* / Q000502:physiology; D005820:Genetic Testing / Q000379:methods; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics* / Q000502:physiology; D009690:Nucleic Acid Conformation; D009691:Nucleic Acid Denaturation / Q000235:genetics; D012313:RNA / Q000235:genetics
D020121:5' Untranslated Regions; D012313:RNA; D004247:DNA; D005293:Ferritins