Since 1998, the GRG has established a broad network of correspondents throughout the world. GRG Correspondents monitor, investigate, and attempt to validate supercentenarian claims in their respective region. Case applications are sent to the GRG Administration Team for review and potential case acceptance. In recognition of their work, please find a partial list of GRG Country Correspondents below:

If you would like to become a GRG representative on national level, a GRG Country Correspondent, and help us validate supercentenarian cases from YOUR native country and/or region, please contact the GRG Administration.


Mr. Nicholas Ruiz Moreno

GRG Correspondent for Argentina since 2015.
Responsible for validation of Casilda Benegas Gallego, the oldest validated Argentine supercentenarian on record.
E-mail: ; Cell phone: (03436) 15412829


Mr. Thomas Breining

GRG Correspondent for Austria since 2008.


Prof. John McCormack

GRG Correspondent for Australia


Prof. Michel Poulain, Ph.D.

GRG Correspondent for Belgium
Emeritus professor at UCLouvain, he is also senior researcher at the Estonian Institute for Population Studies at Tallinn University (Estonia). He has been President of the Société Belge de Démographie (1984-1990) and later of the Association Internationale des Démographes de Langue Française (AIDELF), (1988-2000); the father of the “blue zones” concept

Mr. Peter Vermaelen

GRG Correspondent for Belgium (since 2008)


Mr. Ricardo Pereira Lago

GRG Correspondent for Brazil (since 2015)

Mr. Stanley R. Primmer

Prof. Cassio M. Turra

Mr. Gabe Ainsworth

GRG Correspondent for Brazil

Mr. Tiago Jose Silva

GRG Correspondent for Brazil (since 2016)

Mr. Gerson Diaz

GRG Correspondent for Brazil (since 2020)

Dr. Angelo Jose Goncalves Bos

GRG Correspondent for Brazil (since 2023)
Expert in Biomedical Gerontology, Aging, and Public Health

Mr. Guilherme Matheus de Sousa

GRG Correspondent for Brazil (since 2023)

Minas Gerais; graduate in Environmental Management, teacher and master’s student in Geography.


Mr. Lachezar Zanev

GRG Correspondent for Bulgaria (since 2020)


Prof. Bertrand Desjardins, Ph.D.

GRG Correspondent for Canada
Professor at the University of Montreal


Dr. Anthony Medford, Ph.D

GRG Correspondent for Barbados
University of Southern Denmark


Dr. Danan Gu, Ph.D

GRG Correspondent for China (since 2016)

Czech Republic

Mr. Adam Komenda

GRG Correspondent for the Czech Republic (since July 15, 2023)
Graduate of Law at the University of Western Bohemia


Mr. Waclaw Jan Kroczek, DMD

interim GRG Correspondent for Denmark (since Aug. 15, 2023)
interim GRG Correspondent for Faroe Islands and Greenland


VOICE: +48 600 109 523


Mr. Gordei Korjak

GRG Correspondent for Estonia (since 2023)
Tallinn. Jurist and politician. Graduated from Tallinn University. Master of Laws.



Mr. Antti Hervonen

GRG Correspondent for Finland


Mr. Sylvain Grosgeorge

GRG Correspondent for France (since 2023)

Dr. Jean-Marie Robine, PhD

GRG Correspondent for France


Mr. Thomas Breining

GRG Correspondent for Germany (since 2004)

GRG Correspondent for Austria (since 2004)

Mr. Stefan Jamin

GRG Correspondent for Germany (since 2008)

GRG Correspondent for Eastern Europe
Co-validator of Augusta Holtz (1871-1986), the first person in history who lived beyond 115 years of age.


Ilias Leivaditis

GRG Correspondent for Greece (since 2015)

Prof. Dimitrios Kardamakis, M.D., Ph.D., DMRT

GRG Correspondent for Greece

Department of Radiation Oncology
University of Patras Medical School



Currently vacant


Dr. Ármann Jakobsson

GRG Correspondent for Iceland (since 2023)

University of Iceland

Ármann Jakobsson is professor of early Icelandic literature at the University of Iceland and has been interested in supercentenarians since following news of Halldóra Bjarnadóttir (1873-1981).


Mr. Udaya Revathi Udayashankar

Dr. Raj Kumar, Ph.D.


Ravi Chawla



Mr. Giovanni Alunni

GRG Correspondent for Italy (2003-2009)


Mr. Alfredo Nocera

GRG Correspondent for Italy (since 2023)

interim GRG Correspondent for San Marino (since 2023)
Professional Italian genealogist, member of the APG


Hamish Todd

GRG Correspondent for Japan

British Museum, London, UK

Ken Matsuoka

Stefan Gelow

Dr. D. Craig Wilcox, Ph.D., MHSc, FGSA

GRG Correspondent for Japan, Okinawa Centenarian Study;
Dr. Wilcox has been studying genetic and lifestyle factors associated with healthy aging and longevity for over two decades and has successfully established numerous cross-national research collaborations through the National Institutes of Health and the National Institute on Aging and projects supported by national funding agencies in Japan, such as the Japan Society for Promotion of Sciences, among other sources. He currently serves as Co-Principal Investigator of the Okinawa Centenarian Study and Head of the Okinawa Research Center for Longevity Science R&D, as well as a co-investigator or consultant for several ancillary R-01 funded studies of aging from the Kuakini Honolulu Heart Program. These include the Kuakini Hawaii LIFESPAN and HEALTHSPAN Studies. Dr. Willcox is a fluent speaker of Japanese and has extensive research experience in bio-cultural approaches to healthy aging including, anthropological, epidemiological, and nutritional, with further experience in human population genetics and the study of gene-environment interactions.

Mr. Tom Li

GRG Correspondent for Japan


Mr. Gert Jan Kuiper

GRG Correspondent for the Netherlands (since 2002)
Validator of Hedrikje van Andel-Schipper (1890-2005) and other Dutch supercentenarian cases.

Mr. Jair van Dijk

GRG Correspondent for the Netherlands (since November 2023)


Mr. Waclaw Jan Kroczek, DMD

interim GRG Correspondent for Norway (since Aug. 15, 2023)

Co-validator of Elisabet Ekenaes (1904-2017), the second-oldest person in Norwegian history.


VOICE: +48 600 109 523

Sadly, our GRG Correspondent for Norway, Celvin Ruisdael died in 2012 at the age of 47.


Mr. Waclaw Jan Kroczek, DMD

GRG Correspondent for Poland (since Sept. 13, 2013)
interim GRG Correspondent for Denmark (since Aug. 15, 2023)
interim GRG Correspondent for Sweden (since Aug. 15, 2023)
interim GRG Correspondent for Norway (since Aug. 15, 2023)
GRG Administrative Assistant (Aug. 15, 2015 – Aug. 15, 2018)
GRG Administrator for Case Validation Reports (since Aug. 15, 2018)
Graduated from the Medical University of Silesia where he earned his DMD diploma. Apart from healthy senility and longevity, Waclaw’s interests include social activism, sports and acting. His most notable validations include Israel Kristal (1903-2016) of Poland/Israel, WOM and the oldest Auschwitz survivor, and Tekla Juniewicz (1906-2022) of Ukraine/Poland, the first validated 116-year old person living north to the 50th parallel.
VOICE: +48 600 109 523


Mr. Filipe Prista Lucas

GRG Correspondent for Portugal

Puerto Rico

Ms. Jennie “Jayne” Jimenez

GRG Correspondent for Puerto Rico (since 2015)
Privately, granddaughter of Antonia Gerena Rivera (1900-2015), the great supercenterian from Puerto Rico/USA (Florida)



Dmitry Sudakov

Dr. Leonid Gavrilov, Ph.D.

GRG Correspondent for Russia

University of Chicago


Mr. Dejan Vujić

GRG Correspondent for Serbia (since 2023)
interim GRG Correspondent for Bosnia and Herzegovina (since 2023)
interim GRG Correspondent for Montenegro (since 2023)
interim GRG Correspondent for Kosovo (since 2023)
The validator of Tamara Krutikov (1912-2022), the first validated supercentenarian in Serbia


Mr. Silvo Torkar

GRG Correspondent for Slovenia (since 2010)

Responsible for the validation of Katarina Marinic (1899-2010), the oldest Slovenian person in history.

South Africa

Mrs. Heather MacAlister

GRG Correspondent for the Republic of South Africa (since 2023)
Genealogist for over 35 years. Founder of the Cape Town Family History Society and researcher for TV series such as DNA Journey, Who Do You Think Are UK & South Africa, Australian Story and Finders International.

South Korea

Dr. Jong Bhak, Ph.D.

GRG Correspondent for South Korea
Personal Genomics Institute and Theragen Bio Institute, Director



Sr. Miguel Quesada

GRG Correspondent for Spain (since 2004)


Emilio Ibanez

GRG Correspondent for Spain



Mr. Waclaw Jan Kroczek, DMD

interim GRG Correspondent for Sweden (since Aug. 15, 2023)


VOICE: +48 600 109 523

Mr. Foti Tillo

GRG Correspondent for Sweden

Mr. Victor Bjoerk

GRG Correspondent for Sweden (since 2016)
GRG Administrative Assistant for News
Uppsala, Uppsala County, Sweden
E-mail:; Voice: (0046) 0703821439.


Mr. Flavio Stuber

GRG Correspondent for Switzerland (since 2016)

United Kingdom

Mr. Oliver Trim

GRG Correspondent for the United Kingdom (since 2022)

Currently lives in Somerset, England. Ollie has been interested in supercentenarians for almost 10 years. He enjoys gardening, walking, and spending time with his dog – a black Labrador called Leia.


Mr. Oliver Thorpe

Former GRG Correspondent for the United Kingdom (2016-2022)

United States

Mr. Robert D. Young, MA, MA

GRG member since 1999. Atlanta, Georgia, USA;
Director, GRG Supercentenarian Research and Database Division (This involves managing the other admins, attend conferences representing the GRG, preparing scientific tables and publications, managing all applications, putting them in order, filing the data, and moving cases forward). In addition, he is the GRG Senior Claims Investigator. The GRG representative to the International Database on Longevity (IDL); and
Senior Gerontology Consultant for the Guinness Book of World Records
Voice: (404) 807-0029..

Mr. Louis Epstein

Prof. John R. Wilmoth, Ph.D.

GRG Correspondent for the USA

Demographer of the Center for the Economics and Demography of Aging at UC Berkeley
Professor at the Department of Demography of the University of California at Berkeley. He has also previously served in the Population Division as Chief of the Mortality Section from 2005 to 2007.
Mr. Wilmoth is the author or co-author of more than 50 scientific papers examining various aspects of population dynamics and population issues, including the causes of the historical decline of human mortality, prospects for future trends in life expectancy, the impact of population ageing on public pension and healthcare systems, popular perceptions of population growth and its consequences, and methodologies for estimating and projecting demographic trends. Mr. Wilmoth has also served as a consultant to the World Health Organization and the World Bank from 2009 to 2012, leading the development of new global estimates of maternal mortality. He is a member of the Population Association of America and the International Union for the Scientific Study of Population. He also serves on the editorial boards of some leading demographic journals including Demographic Research and the European Journal of Population.


Mr. Donald B. Gennery

GRG Biostatistician, NASA/JPL; Pasadena, California, USA


Mr. Ethan Unruh

Nebraska, USA, Junior GRG Correspondent for USA


Mr. Mark Muir

GRG Correspondent for the USA
Phoenix, Arizona, USA, Senior Administrator for GRG Website Support



Mr. Esteban Gonzalez Olase

Former GRG Correspondent for Uruguay (2022-2023)
E-mail: ; Phone: +598 999 63 72


Currently vacant

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