Dubrovitsy, Podolsk Region, Moscow Province, 142132 Russia, e-mail n_zinovieva@mail.ru Acknowledgements: The studies were performed with financial support of the Russian Ministry of Education and Science; project ¹ 14.604.21.0062, unique identification ¹ RFMEFI60414X0062 Received April 30, 2016 A b s t r a c t The observed progressive increase of homozygosity in the cultural cattle breeds leads to increased negative impact of LoF-mutations (LoF — loss-of-function) in reducing cow fertility. <...> Significant progress in the identification of LoF-mutations, which are associated with fertility, was achieved with the development of a new approach called «homozygosity mapping» (C. Charlier et al., 2008). <...> This approach allows identifying the chromosomal regions characterized by loss of homozygosity, which are the candidate regions for location of fertility haplotypes associated with embryonic and early post-embryonic mortality. <...> In presented review, it is characterized the haplotypes affecting fertility, which are segregated in Holsteins — the main dairy cattle breed worldwide (bred in 161 countries). <...> In Russia, the ratio of Holstein and holsteinized Black-Pied cattle accounted for more than 65 % of common dairy cattle population. <...> Currently, in the Holstein breed is registered ten fertility haplotypes (HCD, HH0, HH1, HH2, HH3, HH4, HH5, HHB, HHC, HHD), which affect the pregnancy losses and/or associated with embryonic and early post-embryonic mortality at different stages (J.B. Cole et al., 2016). <...> These are intensive use of carrier bulls for artificial insemination, a considerable period from occurrence to the identification of causative mutations (18-59 years), the possible association of carrier status with productive traits. <...> The chromosomal location of the fertility haplotypes is characterized, the haplotype frequencies in North-American Holstein population are presented and the effects of bull carrier status on cow pregnancy rate are shown. <...> It is described the stages of pregnancy and/or the age of calves on which there is the embryonic mortality of affected fetus and/or the death of affected calves. <...> It is shown that more than 5 % of sires used in Russia have had the fathers, which are the carriers of fertility haplotypes. <...> Thus, it is necessary to screen the Russian population of Holstein and holsteinized cattle to detect the carrier status of animals. <...> The role of DNA-diagnostics <...>