A 39-bp deletion polymorphism in PTEN in African American individuals: implications for molecular diagnostic testing.
Germline mutations in the PTEN/MMAC1/TEP1 tumor suppressor gene cause Cowden syndrome (CS), a hereditary hamartoma-tumor syndrome with an increased risk of breast, thyroid, and endometrial cancers, and seemingly unrelated developmental disorders, such as Bannayan-Riley-Ruvalcaba (BRR) syndrome, Proteus, and Proteus-like syndromes. Data to date suggest that irrespective of the clinical presentation, the identification of a PTEN mutation should trigger medical management which includes cancer surveillance. Clinic-based molecular diagnostic testing for germline PTEN mutations has been available for at least 2 years. This study reports on the finding of a previously unobserved heterozygous alteration (IVS7-15-->53del39) found in an African American individual who had features of CS. Further investigation revealed that 12 of 42 (28.6%) African American controls, but not individuals of Caucasian or Japanese origin, also carried this heterozygous 39-bp deletion in PTEN. Due to its location immediately upstream of the splicing site of exon 8, this polymorphism could be mistaken for a deleterious mutation in the PTEN.
Zhou
Xiao-Ping
XP
Clinical Cancer Genetics and Human Cancer Genetics Programs, The Ohio State University, 420 W. 12th Avenue, Columbus, OH 43210, USA.
Hampel
Heather
H
Roggenbuck
Jennifer
J
Saba
Nabil
N
Prior
Thomas W
TW
Eng
Charis
C
D001483:Base Sequence; D044383:Black People / Q000235:genetics*; D017931:DNA Primers / Q000737:chemistry; D016147:Genes, Tumor Suppressor; D018095:Germ-Line Mutation; D006223:Hamartoma Syndrome, Multiple / Q000175:diagnosis* / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007564:Japan / Q000453:epidemiology; D051059:PTEN Phosphohydrolase; D010744:Phosphoric Monoester Hydrolases / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D016715:Proteus Syndrome / Q000175:diagnosis* / Q000235:genetics*; D017384:Sequence Deletion; D025521:Tumor Suppressor Proteins / Q000235:genetics*; D044465:White People / Q000235:genetics; D001741:Black or African American
D017931:DNA Primers; D025521:Tumor Suppressor Proteins; D010744:Phosphoric Monoester Hydrolases; D051059:PTEN Phosphohydrolase; C494929:PTEN protein, human