Misattributed paternity

Misattributed paternity is the situation when a child’s putative father is not the child's biological father. Overall, the incidence of misattributed paternity ranges from about 1% to 2%, though it may be considerably higher in certain populations. Genetic testing for purposes other than establishing paternity has the potential to unintentionally yield information regarding a child’s paternity. This generally occurs in two different scenarios: the first occurs in searches for a suitable bone marrow or organ donor where the patient’s family members are tested; the second is in the course of a genetic-risk assessment for reproductive purposes.

Misattributed paternity is also referred to as false paternity, illegitimacy, non-paternity or paternity fraud, though the latter term suggests that the misattribution was deliberate rather than accidental.[1]

Incidence

The table shows measurements of unsuspected non-paternity rates published since 1957.[2] Early paternity tests were based on informative blood protein variants (blood markers), and since the 1990s, DNA testing has become the standard method. Y chromosome/surname comparisons provide historical non-paternity rates averaged across the entire surname period (circa AD 1300 to the present, for most English family names).

Country Population Sample Size non-paternity percentage Method Bias Reference
UK southern English families 2578 3.7 Blood and other markers not known Edwards 1957[3]
USA Undisputed paternity tests 67 18.0 Blood and other markers not known Sussman and Schatkin 1957[4]
USA Michigan white sample 1417 1.4 Blood and other markers not known Schacht and Gershowitz 1963[5]
USA Michigan black sample 523 10.1 Blood and other markers not known Schacht and Gershowitz 1963[5]
USA Californian white sample 6960 2.7 Blood and other markers not known Peritz and Rus 1972[6]
South America Yanomama tribe 132 9.0 Blood and other markers not known Neel and Weiss 1975[7]
USA Hawaiian families 2839 2.3 Blood and other markers non-participation in sample (−) Ashton 1980[8]
New Zealand Tokelau families (Polynesians) 1983 4.0 Blood and other markers not known Lathrop et al 1983[9]
Mexico Families with newborns 217 2.9 Blood and other markers not known Peñaloza 1986[10]
UK Cystic fibrosis screening 521 1.4 DNA testing non-participation in sample (−) Brock and Shrimpton 1991[11]
France Genetic screening (various) 362 2.8 DNA testing non-participation in sample (−) Le Roux et al 1992[12]
Canada Haemophilia B screening 25 4.0 DNA testing non-participation in sample (−) Poon et al 1993[13]
Switzerland Cystic fibrosis/bone marrow screening 1607 0.8 Mixed methods non-participation in sample (−) Sasse et al 1994[14]
Mexico Nuevo Leon newborns 396 11.8 Blood and other markers not known Cerda-Flores et al 1999[15]
UK Multiple sclerosis screening 744 1.6 DNA testing non-participation in sample (−) Chataway et al 1999[16]
UK Y vs surname comparison (Sykes genealogy) 48 1.3 DNA testing single founder assumed (+) Sykes and Irven 2000[17]
UK Y vs surname comparison (Attenborough genealogy) 1 1.29–3.39 DNA testing single founder assumed (+) King and Jobling 2009[18]
UK Y vs surname comparison (Haythornthwaite genealogy) 1 2.07–4.54 DNA testing single founder assumed (+) King and Jobling 2009[18]
UK Y vs surname comparison (Herrick genealogy) 1 1.00–2.47 DNA testing single founder assumed (+) King and Jobling 2009[18]
UK Y vs surname comparison (Stribling genealogy) 1 1.00–2.87 DNA testing single founder assumed (+) King and Jobling 2009[18]
UK Y vs surname comparison (Swindlehurst genealogy) 1 1.04–2.76 DNA testing single founder assumed (+) King and Jobling 2009[18]
Iraq immigration testing (Kurds) <24097 1.6 DNA testing not known Forster et al 2015[19]
Nigeria immigration testing <24097 8.3 DNA testing not known Forster et al 2015[19]

The rate of non-paternity is commonly quoted to be much higher, around 10% or even more.[20][21][22] Sociologist Michael Gilding has concluded that such high estimates circulated by the media, the paternity testing industry, fathers' rights activists and evolutionary psychologists are inflated.[23][24] He traces many of these estimates back to a 1972 conference discussion:[25]

“We blood-tested some patients in a town in south-east England,” Dr Elliot Philipp told the symposium, “and found that 30 per cent of the husbands could not have been the fathers of their children...” At this point Dr Philipp was interrupted by a judge, who observed that “surely the figure of 30 per cent must be a minimum?” The judge clearly understood that while blood tests could definitively exclude paternity, they could not definitively establish it. This is why experts in paternity testing generally speak of an “exclusion rate” rather than a “non-paternity rate” or “misattributed paternity rate.” Dr Philipp agreed that the figure was “a minimum.” He then explained how he came to be doing the tests. His team was “screening some female patients by testing their husbands for their blood groups” as part of a study about the formation of antibodies. The results surprisingly showed that “30 per cent of the children could not have been fathered by the men whose blood group we analysed.” Another participant asked about the number of people who were tested. Dr Philipp replied, “Not large – between 200 and 300 women – but large enough to give us a real shock.”[26]

Gilding concluded that Dr Philipp's high figure of 30% was more in keeping with the inevitably high incidence of non-paternity in cases where disputed parentage was the reason for the paternity testing. In such cases, other sources have consistently recorded an incidence of 17% to 33% (median of 26.9%), especially among offspring born to younger parents and to unmarried couples, and among those of lower socio-economic status or from certain cultural groups.[2]

Genetic counseling

Main article: Genetic counseling

In the context of a genetic-risk assessment for reproductive purposes a finding of misattributed paternity is more problematic, both ethically and legally. For example, a couple approaches a genetic counselor after the birth of a child with an autosomal recessive disorder (such as Tay Sachs) and both parents must be carriers of the trait. The test reveals that the father is not a carrier, and is therefore not the biological father (unless the disorder was caused by a mutation, a negligible risk). Instead of future children having a 25% chance of being affected, the chance is close to zero. There are issues with the genetic counselor withholding the information, disclosing the misattributed-paternity finding, partially disclosing the information, or addressing the issue before testing as part of the informed consent process.

There is no consensus on a single, appropriate approach a genetic counselor should take with respect to misattributed paternity, and there are proponents for each. A 1983 report of the President's Commission for the Study of Ethical Problems in Medicine and Biomedical and Behavioral Research recommended that genetic counselors employ full disclosure. By contrast, in 1994 the Institute of Medicine’s Committee on Assessing Genetic Risks recommended that the counselor disclose the information only to the mother. The Hereditary Disease Programme of the World Health Organization declared that there is probably never a situation in which the information should be disclosed to the putative father.

Surveys of genetic counselors indicate that an overwhelming majority (96–98.5 percent) would not divulge misattributed paternity results to the presumed father; sixty percent would include information about misattributed paternity on an informed-consent document. Therefore, genetic-counseling custom appears to support telling the mother alone, or withholding misattributed paternity from both parties. Courts often consider custom as evidence of what a reasonable physician would do in similar circumstances (the standard for medical malpractice).

Notes

  1. ↑ Draper, Heather (2005). "Paternity fraud and compensation for misattributed paternity". Journal of Medical Ethics 33 (8): 475–480. doi:10.1136/jme.2005.013268. PMC 2598159. PMID 17664309.
  2. ↑ 2.0 2.1 Bellis MA, Hughes K, Hughes S, Ashton JR (September 2005). "Measuring paternal discrepancy and its public health consequences". J Epidemiol Community Health 59 (9): 749–54. doi:10.1136/jech.2005.036517. PMC 1733152. PMID 16100312.
  3. ↑ Edwards JH (1957) "A critical examination of the reputed primary influence of ABO phenotype on fertility and sex ratio". Br J Prev Soc Med 11:87–89
  4. ↑ Sussman LN, Schatkin SB (1957) "Blood-grouping tests in undisputed paternity proceedings". JAMA 164:249–250
  5. ↑ 5.0 5.1 Schacht LE, Gershowitz H (1963) "Frequency of extra-marital children as determined by blood groups". In: Gedda L, ed. Proceedings of the Second International Congress on Human Genetics. Rome, published by G Mendel, pp. 894–897
  6. ↑ Peritz E, Rust PF (1972) "On the estimation of the nonpaternity rate using more than one blood-group system". Am J Hum Genet 24:46–53.
  7. ↑ Neel JV, Weiss KM (1975) "The genetic structure of a tribal population, the Yanomama Indians". Am J Phys Anthrop 42:25–52
  8. ↑ Ashton GC (1980) "Mismatches in genetic markers in a large family study". Am J Hum Genet 32:601–613
  9. ↑ Lathrop GM, Hooper AB, Huntsman JW, et al. (1983) "Evaluating pedigree data. I. The estimation of pedigree error in the presence of marker mistyping". Am J Hum Genet 35:241–262
  10. ↑ Peñaloza R, Núñez C, Silvia A, et al. (1986) "Frequency of illegitimacy in a sample of the Mexican population". La Rev Invest Clin (Méx) 38:287–291
  11. ↑ Brock DJH, Shrimpton AE (1991) "Non-paternity and prenatal genetic screening". Lancet 338:1151
  12. ↑ Le Roux M, Pascal O, Andre M, et al. (1992) "Non-paternity and genetic counselling". Lancet 340:607
  13. ↑ Poon M, Anand S, Fraser BM, et al. (1993) "Hemophilia B carrier determination based on family-specific mutation detection by DNA single-strand conformation analysis". J Lab Clin Med 122:55–63
  14. ↑ Sasse G, Müller H, Chakraborty R, et al. (1994) "Estimating the frequency of nonpaternity in Switzerland". Hum Hered 44:337–43
  15. ↑ Cerda-Flores RM, Barton SA, Marty-Gonzalez LF, et al. (1999) "Estimation of nonpaternity in the Mexican population of Nuevo Leon: a validation study with blood group markers". Am J Phys Anthropol 109:281–293
  16. ↑ Chataway J, Sawser S, Feakes R, et al. (1999) "A screen of candidates from peaks of linkage: evidence for the involvement of myeloperoxidase in multiple sclerosis". J Neuroimmunol 98:208–213
  17. ↑ Sykes B, Irven C (2000) "Surnames and the Y chromosome". Am J Hum Genet 66:1417-1419
  18. ↑ 18.0 18.1 18.2 18.3 18.4 King TE, Jobling MA (2009) "Founders, drift, and infidelity: the relationship between Y chromosome diversity and patrilineal surnames". Mol Biol Evol 26:1093-1102.
  19. ↑ 19.0 19.1 Forster P, Hohoff C, Dunkelmann B, Schürenkamp M, Pfeiffer H, Neuhuber F, Brinkmann B. (2015) "Elevated germline mutation rate in teenage fathers". Proc Biol Sci 282:20142898
  20. ↑ Macintyre S and Sooman A (1991). "Non-paternity and prenatal genetic screening". Lancet 338 (8771): 869–871. doi:10.1016/0140-6736(91)91513-T. PMID 1681226.
  21. ↑ Neale MC, Neale BM, Sullivan PF (2002). "Nonpaternity in Linkage Studies of Extremely Discordant Sib Pairs". Am J Hum Genet 70 (2): 526–529. doi:10.1086/338687. PMC 384925. PMID 11745068.
  22. ↑ Rincon P (11 February 2009). "Study debunks illegitimacy 'myth'". BBC News. Retrieved 11 February 2009.
  23. ↑ Gilding, Michael (2005). "Rampant misattributed paternity: the creation of an urban myth". People and Place (Monash University) 13 (12): 1–11.
  24. ↑ Gilding, M. (2009). "Paternity Uncertainty and Evolutionary Psychology: How a Seemingly Capricious Occurrence Fails to Follow Laws of Greater Generality". Sociology 43: 140–691. doi:10.1177/0038038508099102.
  25. ↑ Philipp EE (1973) "Discussion: moral, social and ethical issues". In: Wolstenholme GEW, Fitzsimons DW, eds. Law and ethics of AID and embryo transfer. Ciba Foundation symposium. Vol 17. London: Associated Scientific 63–66
  26. ↑ Gilding, Michael (26 July 2011). "The fatherhood myth: Michael Gilding unravels the uncertain data about mistaken paternity". The inside story. Retrieved 10 November 2012.

Sources