  The first fermion family might play a special role in understanding the
physics of flavour. This possibility is suggested by the observation that the
up-down splitting within quark families increases with the family number: $
m_u\sim m_d$, $m_c>m_s$, $m_t\gg m_b$. We construct a model that realizes this
feature of the spectrum in a natural way. The inter-family hierarchy is first
generated by radiative phenomena in a sector of heavy isosinglet fermions and
then transferred to quarks by means of a universal seesaw. A crucial role is
played by left-right parity and up-down isotopic symmetry. No family symmetry
is introduced. The model implies $m_u/m_d>$ 0.5 and the Cabibbo angle is forced
to be $\sim\sqrt{m_d/m_s}$. The top quark is naturally in the 100 GeV range,
but not too heavy: $m_t<$ 150 GeV. Inspired by the mass matrices obtained in
the model for quarks, we suggest an ansatz also including charged leptons. The
differences between $u$-, $d$- and $e$-type fermions are simply parametrized by
three complex coefficients $\eps{u}$, $\eps{d}$ and $\eps{e}$. Additional
consistent predictions are obtained: $m_s$=100-150 MeV and $m_u/m_d<$ 0.75.
