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939 citation(s) found for "Tan, Qi".

The common African American polymorphism SCN5A-S1103Y interacts with mutation SCN5A-R680H to increase late Na current
Cheng, Jianding , Tester, David J. , Tan, Bi-Hua, Valdivia, Carmen R. , Kroboth, Stacie , Ye, Bin , January, Craig T., Makielski, Jonathan C., Tan, Bi‐Hua , Ackerman, Michael

Mayo Clinic

Physiological Genomics | March 8, 2011 | Volume: 43 | Issue: 9 | Pages: 461-466

10.1152/physiolgenomics.00198.2010 | PMID 21385947 Get It

The common polymorphism SCN5A-S1103Y (∼13% allelic frequency in African Americans) is a risk factor for arrhythmia, sudden unexplained death (SUD), and sudden infant death syndrome. Prompted by a case of autopsy-negative SUD in a 23-year-old African American man who collapsed while playing football, we hypothesized that S1103Y interacted with other SCN5A variants to pathologically modify sodium current ( I Na ). Mutational analysis of arrhythmia-associated genes in the victim revealed the variants SCN5A-R680H and SCN5A-S1103Y. These variants were made both separately and in the same cDNA construct of the alternative splice variant backgrounds (SCN5A-Q1077del and Q1077) and expressed in HEK293 cells. In the most abundant SCN5A-Q1077del, late I Na for S1103Y alone was not significantly different from wild type (WT). However, late I Na for R680H, R680H+S1103Y (coexpressed), and R680H/S1103Y (on the same cDNA) was increased 2.1-, 3.4-, and 3.6-fold, respectively, compared with WT. Intracellular acidosis (pH 6.7) increased late I Na for S1103Y, R680H, R680H+S1103Y, and R680H/S1103Y by 2.2-, 2.4-, 5.0-, and 5.5-fold, respectively, compared with WT at pH 6.7. Expression in the less abundant SCN5A-Q1077 showed no increased late I Na . This is the initial report of a functional interaction for the common polymorphism S1103Y with another mutation in the major transcript Q1077del of SCN5A. The “double hit” and environmental factor of acidosis may have converged to cause arrhythmic sudden death in this case.
N0539 Phase II Trial of Fulvstrant and Bevacizumab in Patients with Metastatic Breast Cancer Previously Treated with an Aromatase Inhibitor: A North Central Cancer Treatment Group Trial.
Tan, Winston , Flynn, Patrick J. , Steen, Preston D. , Anderson, D. Mark , Rowland, Kendrith M. , Nothfeldt, D., Lingle, Wilma L., Copland, John A. , Perez, Edith A. , Dueck, Amylou C.

Mayo Clinic

Cancer Research | December 30, 2010 | Volume: 69 | Issue: 24_Supplement | Pages: 4096-4096

10.1158/0008-5472.sabcs-09-4096 Get It

Abstract Background: Treatment of aromatase refractory metastatic breast cancer (MBC) is difficult and challenging. Estrogen receptor (ER) resistance causes enhanced expression of the vascular endothelial growth factor (VEGF).Several studies have shown that the ER interacts with the VEGF pathway and is an important mechanism of resistance. Therefore we embarked on a phase II study of fulvestrant, a complete ER suppressor and bevacizumab, a well studied VEGF monoclonal antibody in aromatase refractory MBC patients. Methods: A single stage phase II study with an interim analysis of fulvestrant and bevacizumab was conducted with these objectives: 6 month progression-free survival rate (PFS), tumor response, toxicity, and overall survival. Regimen: fulvestrant 250 mg day1 and 15 (cycle 1) then day 1 (cycle 2 and beyond) and bevacizumab 10mg/kg days 1 and 15 of each 4 weeks is a cycle. Results: At the time of interim analysis, 11/20 evaluable patients achieved 3-month progression-free survival status while remaining on treatment for at least 3 months, not meeting the protocol specified efficacy requirements and thus halting accrual. 36 patients were enrolled from September 2007-December 2008; 33 patients were evaluable. Number of prior metastatic chemotherapy regimens: 0 in 26 patients and 1 in 7 patients. 22 (67%) patients received prior hormonal therapy in the metastatic setting. 18 (55%) had measurable disease. A median of 6 cycles (range 1-19) were administered. 12/33 evaluable patients (95% CI:20-55%) achieved 6-month progression-free survival status while remaining on treatment for a least 6 months. Among 18 patients with measurable disease, 2 (11%) patients CI:1.4-35%) had a confirmed tumor reponse (both PR). Additionally, 2 patients had stable disease for greater than 6 months, for a clinical benefit rate of 22%. Median follow up was 8.5 months (range 1.7-17.5 months). Median progression-free survival was 6.2 months (95% CI:5.4-10.1 months). The 6 -month overall survival rate was 84.8% (95% CI 73.5-98%). The median dose level administered was 250 mg for fulvestrant and 10 mg/kg for bevacizumab for cycles 1-19. The most common grade 3/4 adverse events (AEs) were hypertension 2 (6%), headache pain 2 (6%), and confusion 2 (6%). There was 1 grade 5 central nervous system hemorrhage. 13 (39%) patients experienced a grade 3 non-hematologic AE and 4 (12%) experience a grade 4+ non-hematologic AE. Conclusion: Fulvestrant/bevacizumab is safe and tolerable. Although this regimen did not meet its statistical endpoint, 22% of evaluable patients with aromatase refractory diesease achieved clinical benefit with minimal toxicity. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4096.
The utility of preoperative breast magnetic resonance imaging in invasive breast cancer according to HER2 status.
McLaughlin, SA, Vallow, LA, Hines, SL, Tan, Winston

Mayo Clinic

Cancer Research | December 30, 2010 | Volume: 69 | Issue: 2_Supplement | Pages: 4020

10.1158/0008-5472.sabcs-4020 Get It

Abstract Abstract #4020 Background: HER2 positive (HER2+) breast cancer accounts for 20% of all breast cancer and is an independent adverse prognostic factor. Breast magnetic resonance imaging (MRI) has been shown to identify additional mammographically occult ipsilateral (I/L) and contralateral (C/L) disease, however indications for preoperative MRI in patients with newly diagnosed breast cancer are not standardized. While invasive lobular cancer, younger patient age, and increased breast density have been suggested as routine indications, the role of preoperative MRI according to HER2 status has not been evaluated.
 Methods: All patients with invasive breast cancer who underwent preoperative MRI between January 2003 and December 2007 were reviewed. Retrospective chart review was performed to collect clinical, radiographic, and pathologic data. The incidence of additional I/L or C/L malignacy was calculated. Additionally, changes in surgical management because of MRI findings were recorded.
 Results: Of the 401 women with invasive breast cancer undergoing preoperative breast MRI, 51 (13%) had HER2+ tumors. The average age at the time of MRI was similar in both groups. HER2+ patients were more likely to have nodal disease, and tumors with higher rates of lymphovascular invasion or extensive intraductal components.
 
 When compared to HER2- patients, more HER2+ patients had additional ipsilateral MRI abnormalities. A second ipsilateral cancer was found in 31% of HER2+ patients compared to 25% of HER2- patients. When analyzed according to ER status, HER2+/ ER- patients were more likely to have an additional site of cancer compared to HER2+/ER+ patients (42% vs 23%). Conversely, among HER2- patients, rates of additional ipsilateral cancer were similar for HER2-/ER+ (26%) and HERr2-/ER- (23%) patients. Of the 216 patients (HER2+ and HER2-) with additional ipsilateral MRI findings (benign or malignant), 125/216 (58%) patients were deemed appropriate breast conservation (BCT) candidates after MRI. However, BCT was only chosen in 84/125 (67%) patients. Additional contralateral disease was documented in 8% of HER2+ versus 5% of HER2- patients.
 Conclusions: HER2 positivity remains and important prognostic factor for women with breast cancer. Indications for routine preoperative MRI are unclear. In patients with newly diagnosed Her2+ invasive breast cancer routine preoperative MRI may be valuable in the subset of patients who are also ER-. Further study is needed to determine the influence of MRI on patient decisions for surgical therapy. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4020.
A multi-center phase II study of three doses of TAS-108 in postmenopausal women with advanced breast carcinoma following first or second line endocrine therapy.
Buzdar, Aman U. , Tan-Chiu, Elizabeth, Schwartzberg, L., Ellis, Megan , Garin, A., Ingle, JN, Carlson, R.W., Pérez, A

Mayo Clinic

Cancer Research | December 30, 2010 | Volume: 69 | Issue: 2_Supplement | Pages: 2131

10.1158/0008-5472.sabcs-2131 Get It

Abstract Abstract #2131 Introduction: TAS-108 is an oral steroidal anti-estrogen agent that selectively inhibits ERα and is mainly metabolized by CYP3A4. The purpose of this study is to investigate the efficacy and safety of TAS-108 administrated orally in three dose levels in patients with locally advanced, locally recurrent inoperable or metastatic breast carcinoma (BC) in four countries (USA, Russia, Mexico and Chile).
 Methods: Postmenopausal women with confirmed ER and/or PgR positive BC who had previously responded to one or two standard endocrine therapies, with or without one prior chemotherapy were randomly assigned to three doses of TAS-108, 40 mg, 80 and 120 mg daily. Using a modified Panageas' optimal two-stage trinomial design, the enrollment of 60 evaluable patients (first-stage: 19) was required to each individual dose group. Tumor response was assessed every 8 weeks according to RECIST criteria. Adverse events (AEs) were graded by CTC-AE v3.0.
 Results: A total of 146 patients with mean age of 63 years old were enrolled with 61 patients in the 40 mg group and 66 in the 80 mg group. The 120 mg group was terminated at the end of stage 1 with 19 patients enrolled due to lack of efficacy. The mean duration of study treatment was 172 days for the 40 mg group and 160 days for the 80 mg group. Partial response (PR) was documented in 6 (10%) patients in the 40 mg group and 4 (6.7%) patients in the 80 mg group. The rate of disease stabilization (CR+PR+SD) reported by the investigators was 43% (95%CI, 31%,56%) in the 40 mg group and 45% (95%CI, 32%,58%) in the 80 mg group. Adjudicated clinical benefit (CR+PR+SD more than 24 wks) was observed in 22% of patients in the 40 mg group and 20% of patients in the 80 mg group. Clinical benefit was achieved in 25% of patients with 1 prior hormonal therapy and 15% of patients with more than one line of prior hormonal therapy. Median time to progression (TTP): 15 weeks for the 40 mg group and 15.9 weeks for the 80 mg group. Median duration of clinical benefit was 32 weeks in the 40 mg group and 64 weeks in the 80 mg group. In the 40/80/120 mg groups, the commonly reported treatment-related AEs included nausea (15%/11%/16%), fatigue (10%/11%/16%), headache (10%/6%/16%), hot flushes (10%/5%/32%), diarrhea (2%/6%/5%), constipation (3%/3%/5%), and arthralgia (2%/5%/11%). No endometrial cancer and treatment-related deaths occurred during the study.
 Conclusions: TAS-108 has demonstrated anti-tumor activity in this population and was generally well tolerated. The 40 mg dose was chosen as the recommended dose for future clinical evaluation in patients with advanced breast cancer. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2131.
Prognosis and Outcome of Small (≤1 cm), Node-Negative Breast Cancer on the Basis of Hormonal and HER-2 Status
Amar, Surabhi, McCullough, Ann E. , Tan, Winston , Geiger, Xochiquetzal J., McNeil, Rebecca B. , Coppola, Kyle , McLaughlin, Sarah A. , Palmieri, Frances M., Perez, Edith A. , Boughey, Judy C.

Mayo Clinic

The Oncologist | October 8, 2010 | Volume: 15 | Issue: 10 | Pages: 1043-1049

10.1634/theoncologist.2010-0036 | PMID 20930097 Get It

Abstract Long-term outcomes and hence the role of adjuvant therapy in patients with small (≤1 cm), node-negative breast cancer remain unclear. This study's objective was to evaluate whether human epidermal growth factor receptor (HER)-2 status is an independent, poor prognostic marker in patients with these tumors and to identify a subgroup of patients with these small tumors who might benefit from adjuvant systemic therapy. All patients with a diagnosis of a node-negative breast tumor measuring ≤1 cm and available HER-2 test results between January 1, 2001, and December 31, 2005, at the three Mayo Clinic sites were identified. Clinicopathologic data were compared in three groups: HER-2−, HER-2+, and triple-negative (TN) tumors. Of the 421 tumors identified, 364 (86.5%) were HER-2−, 28 (6.7%) were HER-2+, and 29 (6.9%) were TN. The median follow-up time was 1,015 days (range, 1–2,549 days). Groups were balanced in terms of patient age and tumor histology. Eleven patients with HER-2− tumors (3.0%), seven with HER-2+ tumors (25.0%), and eight with TN tumors (27.6%) received adjuvant chemotherapy. Follow-up data were available for 357, 28, and 28 patients in the three groups, respectively. Death rates in the three groups were 6.4% (23 of 357) (one recurrence-related death), 0% (0 of 28), and 7.1% (2 of 28) (one recurrence-related death), respectively. During follow-up, the tumor recurred in nine patients: four were HER-2− tumors (1.1%), two were HER-2+ tumors (7.1%), and three were TN tumors (10.7%). Patients with small, node-negative breast tumors have an excellent prognosis, but HER-2+ and TN tumors appear to have a higher recurrence rate, warranting consideration for broad use and optimization of systemic adjuvant treatments.
International Society for Sexual Medicine’s Guidelines for the Diagnosis and Treatment of Premature Ejaculation
Althof, Stanley E., Abdo, Carmita Helena Najjar , Dean, John, Hackett, Geoff , McCabe, Marita P. , McMahon, Chris G., Rosen, Raymond C., Sadovsky, Richard, Waldinger, Marcel D., Becher, Edgardo, Broderick, Gregory A. , Buvat, Jacques, El-Meliegy, Amr, Hellstrom, Wayne J.G. , Incrocci, Luca , Jannini, Emmanuele A. , Park, Kwangsung , Parish, Sharon J. , Porst, Hartmut, Segraves, Robert, Sharlip, Ira D., Simonelli, Chiara , Tan, Hui Meng, Buvat, Jacques, Goldstein, Irwin , Giuliano, François , Rowland, David L.

Mayo Clinic

The Journal of Sexual Medicine | September 13, 2010 | Volume: 7 | Issue: 9 | Pages: 2947-2969

10.1111/j.1743-6109.2010.01975.x | PMID 21050394 Get It

ABSTRACTIntroductionOver the past 20 years our knowledge of premature ejaculation (PE) has significantly advanced. Specifically, we have witnessed substantial progress in understanding the physiology of ejaculation, clarifying the real prevalence of PE in population-based studies, reconceptualizing the definition and diagnostic criterion of the disorder, assessing the psychosocial impact on patients and partners, designing validated diagnostic and outcome measures, proposing new pharmacologic strategies and examining the efficacy, safety and satisfaction of these new and established therapies. Given the abundance of high level research it seemed like an opportune time for the International Society for Sexual Medicine (ISSM) to promulgate an evidenced-based, comprehensive and practical set of clinical guidelines for the diagnosis and treatment of PE.AimDevelop clearly worded, practical, evidenced-based recommendations for the diagnosis and treatment of PE for family practice clinicians as well as sexual medicine experts.MethodReview of the literature.ResultsThis article contains the report of the ISSM PE Guidelines Committee. It affirms the ISSM definition of PE and suggests that the prevalence is considerably lower than previously thought. Evidence-based data regarding biological and psychological etiology of PE are presented, as is population-based statistics on normal ejaculatory latency. Brief assessment procedures are delineated and validated diagnostic and treatment questionnaires are reviewed. Finally, the best practices treatment recommendations are presented to guide clinicians, both familiar and unfamiliar with PE, in facilitating treatment of their patients.ConclusionDevelopment of guidelines is an evolutionary process that continually reviews data and incorporates the best new research. We expect that ongoing research will lead to a more complete understanding of the pathophysiology as well as new efficacious and safe treatments for this sexual dysfunction. Therefore, it is strongly recommended that these guidelines be re-evaluated and updated by the ISSM every 4 years.
Genetic variants near TIMP3 and high-density lipoprotein–associated loci influence susceptibility to age-related macular degeneration
Stambolian, Dwight, Edwards, Albert O., Branham, Kari , Othman, Mohammad , Jakobsdóttir, Jóhanna , Tosakulwong, Nirubol , Pericak‐Vance, Margaret A. , Klein, Michael L. , Tan, Perciliz L. , Kanda, Atsuhiro , Kopplin, Laura J. , Li, Yanming , Augustaitis, Katherine J., Karoukis, Athanasios J., Scott, William K. , Agarwal, Anita , Kovach, Jaclyn L. , Postel, Eric A. , Brooks, Matthew, Baratz, Keith H. , Brown, William L. , Brucker, Alexander J., Orlin, Anton, Brown, Gary C. , Ho, Allen C. , Regillo, Carl D. , Donoso, Larry A., Tian, Lifeng , Kaderli, Brian, Hadley, Dexter , Hagstrom, Stephanie A. , Peachey, Neal S. , Klein, Ronald , Klein, Barbara E.K. , Gotoh, Norimoto, Yamashiro, Kenji , Ferris, Frederick L. , Fagerness, Jesen, Reynolds, Robyn, Farrer, Lindsay A. , Kim, Ivana K. , Miller, Joan W. , Cortón, Marta , Carracedo, Ángel , Sánchez‐Salorio, Manuel, Pugh, Elizabeth, Doheny, Kimberly F. , Brión, Marı́a , Weeks, Daniel E. , Zack, Donald J. , Heckenlively, John R., Yoshimura, Nagahisa , Iyengar, Sudha K. , Francis, Peter J. , Katsanis, Nicholas , Seddon, Johanna M. , Haines, Jonathan L. , Abecasis, Gonçalo R. , Swaroop, Anand , Johnson, Robert N., Ai, Everett, McDonald, H. Richard , Stolarczuk, Margaret, Pavan, Peter R., Billiris, Karina K., Iyer, Mohan , Menosky, Matthew M., Pautler, Scott E. , Millard, Sharon M., Hubbard, G. Baker , Aaberg, Thomas , DuBois, Lindy, Lyon, Alice T., Anderson-Nelson, Susan, Jampol, Lee M. , Muñana, Annie, Rozenbajgier, Zuzanna, Orth, David H., Cohen, Jack, MacCumber, Matthew, Figliulo, Celeste, Porcz, Liz, Folk, James C. , Boldt, H. Culver , Russell, Stephen R. , Ivins, Rachel, Hinz, Connie J., Bloom, Steve, Jaegers, Ken, Kritchman, Brian, Whittington, Greg K., Frederick, Albert R., Morley, Michael G., Topping, Trexler M., Davis, Heather L., Bressler, Susan B., Bressler, Neil M. , Doll, W T Jr, Trese, Michael T. , Garretson, Bruce R., Ruby, Alan, Osentoski, Tammy, Ruszczyk, Margaret, Grand, G., Joseph, Daniel P., Shah, Gaurav K. , Nobel, Ginny, Antoszyk, Andrew N., Stallings, Alison H, Singerman, Lawrence J. , Miller, David T. , Novák, Michael, Pendergast, Scott, Zegarra, Hernando, Schura, Stephanie A., Smith-Brewer, Sheila, Davidorf, Frederick H., Chorich, Louis J., Salerno, Jill, Dreyer, Richard F., Ma, Colin, Kopfer, Marcia, Wilson, David J. , Nolte, Susan K., Grunwald, Juan E. , Dunaief, Josh, Fine, Stuart L., Maguire, Albert M. , Stoltz, Robert A., McRay, Monique, Fish, Gary E., Anand, Rajiv, Spencer, Rand , Arnwine, Jean, Chandra, Suresh R., Blodi, Barbara, Gottlieb, Justin L., Ip, Michael S. , Nork, T. Michael , Perry-Raymond, Jennie, Brightwell-Arnold, Mary, Harkins, Sandra, Peskin, Ellen, Ying, Gui‐Shuang , Kurinij, Natalie, Chen, Wei , Campochiaro, Peter A. , Conley, Yvette P. , Schwartz, Stephen G. , DeAngelis, Margaret M. , Chew, Emily Y. , Gorin, Michael B. , Menosky, Matthew M., Weinberg, David V. , Barr, Charles C. , Heier, Jeffrey S. , Capone, A. , Hassan, T. , McCannel, Colin A. , Blinder, Kevin J. , Holekamp, Nancy M. , Browning, David J. , Chambers, Robert , Altaweel, Michael M. , Maguire, Maureen G. , Weeks, Daniel E , Brion, María , Abecasis, Gonçalo

Mayo Clinic

Proceedings of the National Academy of Sciences | April 12, 2010 | Volume: 107 | Issue: 16 | Pages: 7401-7406

10.1073/pnas.0912702107 | PMID 20385819 Get It

We executed a genome-wide association scan for age-related macular degeneration (AMD) in 2,157 cases and 1,150 controls. Our results validate AMD susceptibility loci near CFH ( P < 10 −75 ), ARMS2 ( P < 10 −59 ), C2/CFB ( P < 10 −20 ), C3 ( P < 10 −9 ), and CFI ( P < 10 −6 ). We compared our top findings with the Tufts/Massachusetts General Hospital genome-wide association study of advanced AMD (821 cases, 1,709 controls) and genotyped 30 promising markers in additional individuals (up to 7,749 cases and 4,625 controls). With these data, we identified a susceptibility locus near TIMP3 (overall P = 1.1 × 10 −11 ), a metalloproteinase involved in degradation of the extracellular matrix and previously implicated in early-onset maculopathy. In addition, our data revealed strong association signals with alleles at two loci ( LIPC , P = 1.3 × 10 −7 ; CETP , P = 7.4 × 10 −7 ) that were previously associated with high-density lipoprotein cholesterol (HDL-c) levels in blood. Consistent with the hypothesis that HDL metabolism is associated with AMD pathogenesis, we also observed association with AMD of HDL-c—associated alleles near LPL ( P = 3.0 × 10 −3 ) and ABCA1 ( P = 5.6 × 10 −4 ). Multilocus analysis including all susceptibility loci showed that 329 of 331 individuals (99%) with the highest-risk genotypes were cases, and 85% of these had advanced AMD. Our studies extend the catalog of AMD associated loci, help identify individuals at high risk of disease, and provide clues about underlying cellular pathways that should eventually lead to new therapies.
Stem cell transplantation in patients with autonomic neuropathy due to primary (AL) amyloidosis
Dingli, David , Kumar, Shaji , Dispenzieri, Angela , Hayman, Suzanne R. , Lacy, Martha Q. , Gastineau, D A, Tan, Timothy Shao Ern , Buadi, Francis K. , Hogan, William J. , Gertz, Morie A. , Dispenzieri, Angela , Dingli, David

Mayo Clinic

Neurology | March 15, 2010 | Volume: 74 | Issue: 11 | Pages: 913-918

10.1212/wnl.0b013e3181d55f4d | PMID 20231668 Get It

α1-Syntrophin Mutations Identified in Sudden Infant Death Syndrome Cause an Increase in Late Cardiac Sodium Current
Cheng, Jianding , Norstrand, David W. Van, Medeiros‐Domingo, Argelia , Valdivia, Carmen R. , Tan, Bi‐Hua , Ye, Bin , Kroboth, Stacie , Vatta, Matteo , Tester, David J. , January, Craig T., Makielski, Jonathan C., Ackerman, Michael J. , Medeiros-Domingo, Argelia

Mayo Clinic

Circulation: Arrhythmia and Electrophysiology | September 13, 2009 | Volume: 2 | Issue: 6 | Pages: 667-676

10.1161/circep.109.891440 | PMID 20009079 Get It

Background— Sudden infant death syndrome (SIDS) is a leading cause of death during the first 6 months after birth. About 5% to 10% of SIDS may stem from cardiac channelopathies such as long-QT syndrome. We recently implicated mutations in α1-syntrophin (SNTA1) as a novel cause of long-QT syndrome, whereby mutant SNTA1 released inhibition of associated neuronal nitric oxide synthase by the plasma membrane Ca-ATPase PMCA4b, causing increased peak and late sodium current ( I Na ) via S-nitrosylation of the cardiac sodium channel. This study determined the prevalence and functional properties of SIDS-associated SNTA1 mutations. Methods and Results— Using polymerase chain reaction, denaturing high-performance liquid chromatography, and DNA sequencing of SNTA1 ’s open reading frame, 6 rare (absent in 800 reference alleles) missense mutations (G54R, P56S, T262P, S287R, T372M, and G460S) were identified in 8 (≈3%) of 292 SIDS cases. These mutations were engineered using polymerase chain reaction–based overlap extension and were coexpressed heterologously with SCN5A, neuronal nitric oxide synthase, and PMCA4b in HEK293 cells. I Na was recorded using the whole-cell method. A significant 1.4- to 1.5-fold increase in peak I Na and 2.3- to 2.7-fold increase in late I Na compared with controls was evident for S287R-, T372M-, and G460S-SNTA1 and was reversed by a neuronal nitric oxide synthase inhibitor. These 3 mutations also caused a significant depolarizing shift in channel inactivation, thereby increasing the overlap of the activation and inactivation curves to increase window current. Conclusions— Abnormal biophysical phenotypes implicate mutations in SNTA1 as a novel pathogenic mechanism for the subset of channelopathic SIDS. Functional studies are essential to distinguish pathogenic perturbations in channel interacting proteins such as α1-syntrophin from similarly rare but innocuous ones.